diff --git a/Cargo.lock b/Cargo.lock
index 9168b8d..a54dede 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5,10 +5,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "aho-corasick"
-version = "0.6.4"
+version = "0.6.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -25,14 +25,9 @@ dependencies = [
 ]
 
 [[package]]
-name = "atty"
-version = "0.2.8"
+name = "autocfg"
+version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
-]
 
 [[package]]
 name = "bitflags"
@@ -78,6 +73,14 @@ dependencies = [
  "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "cloudabi"
+version = "0.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "coco"
 version = "0.1.1"
@@ -193,7 +196,7 @@ name = "dwmapi-sys"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -212,14 +215,11 @@ dependencies = [
 
 [[package]]
 name = "env_logger"
-version = "0.5.6"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "atty 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "humantime 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "termcolor 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -247,6 +247,11 @@ dependencies = [
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "fuchsia-cprng"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "fuchsia-zircon"
 version = "0.3.3"
@@ -266,7 +271,7 @@ name = "gdi32-sys"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -382,14 +387,6 @@ dependencies = [
  "x11-dl 2.17.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "humantime"
-version = "1.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "quick-error 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "image"
 version = "0.18.0"
@@ -514,11 +511,8 @@ dependencies = [
 
 [[package]]
 name = "memchr"
-version = "2.0.1"
+version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
-]
 
 [[package]]
 name = "memmap"
@@ -538,7 +532,7 @@ dependencies = [
  "find_folder 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "fps_counter 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "piston_window 0.75.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "quickcheck 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quickcheck 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -779,19 +773,15 @@ dependencies = [
  "num-iter 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "quick-error"
-version = "1.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "quickcheck"
-version = "0.6.2"
+version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "env_logger 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "env_logger 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -819,6 +809,102 @@ dependencies = [
  "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rand"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_jitter 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_os 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_pcg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "rand_hc"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_isaac"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_jitter"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_os"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_pcg"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_xorshift"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rayon"
 version = "0.8.2"
@@ -839,6 +925,14 @@ dependencies = [
  "rand 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rdrand"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "read_color"
 version = "1.0.0"
@@ -850,31 +944,31 @@ version = "0.1.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "redox_termios"
-version = "0.1.1"
+name = "regex"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "redox_syscall 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)",
+ "aho-corasick 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "utf8-ranges 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "regex"
-version = "0.2.10"
+name = "regex-syntax"
+version = "0.6.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "aho-corasick 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex-syntax 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "thread_local 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "utf8-ranges 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ucd-util 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "regex-syntax"
-version = "0.5.3"
+name = "rustc_version"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "ucd-util 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -897,6 +991,19 @@ name = "scopeguard"
 version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "semver"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "semver-parser"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "serde"
 version = "0.9.15"
@@ -956,7 +1063,7 @@ name = "shell32-sys"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1022,31 +1129,12 @@ dependencies = [
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "termcolor"
-version = "0.3.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "wincolor 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "termion"
-version = "1.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_syscall 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "thread_local"
-version = "0.3.5"
+version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "unreachable 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1059,26 +1147,18 @@ name = "unicode-xid"
 version = "0.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "unreachable"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "user32-sys"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "utf8-ranges"
-version = "1.0.0"
+version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -1089,11 +1169,6 @@ dependencies = [
  "piston-float 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "void"
-version = "1.0.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "wayland-client"
 version = "0.9.10"
@@ -1185,14 +1260,6 @@ name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "wincolor"
-version = "0.1.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "winit"
 version = "0.8.3"
@@ -1246,10 +1313,10 @@ dependencies = [
 
 [metadata]
 "checksum adler32 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6cbd0b9af8587c72beadc9f72d35b9fbb070982c9e6203e46e93f10df25f8f45"
-"checksum aho-corasick 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "d6531d44de723825aa81398a6415283229725a00fa30713812ab9323faa82fc4"
+"checksum aho-corasick 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)" = "1e9a933f4e58658d7b12defcf96dc5c720f20832deebe3e0a19efd3b6aaeeb9e"
 "checksum android_glue 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "000444226fcff248f2bc4c7625be32c63caccfecc2723a2b9f78a7487a49c407"
 "checksum arrayvec 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "2f0ef4a9820019a0c91d918918c93dc71d469f581a49b47ddc1d285d4270bbe2"
-"checksum atty 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "af80143d6f7608d746df1520709e5d141c96f240b0e62b0aa41bdfb53374d9d4"
+"checksum autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a6d640bee2da49f60a4068a7fae53acde8982514ab7bae8b8cea9e88cbcfd799"
 "checksum bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "aad18937a628ec6abcd26d1489012cc0e18c21798210f491af69ded9b881106d"
 "checksum bitflags 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "4efd02e230a02e18f92fc2735f44597385ed02ad8f831e7c1c1156ee5e1ab3a5"
 "checksum bitflags 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b3c30d3802dfb7281680d6285f2ccdaa8c2d8fee41f93805dba5c4cf50dc23cf"
@@ -1258,6 +1325,7 @@ dependencies = [
 "checksum byteorder 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ff81738b726f5d099632ceaffe7fb65b90212e8dce59d518729e7e8634032d3d"
 "checksum cfg-if 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "d4c819a1287eb618df47cc647173c5c4c66ba19d888a6e50d605672aed3140de"
 "checksum cgl 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "86765cb42c2a2c497e142af72517c1b4d7ae5bb2f25dfa77a5c69642f2342d89"
+"checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
 "checksum coco 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c06169f5beb7e31c7c67ebf5540b8b472d23e3eade3b2ec7d1f5b504a85f91bd"
 "checksum cocoa 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)" = "4047fed6536f40cc2ae5e7834fb38e382c788270191c4cd69196f89686d076ce"
 "checksum color_quant 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a475fc4af42d83d28adf72968d9bcfaf035a1a9381642d8e85d8a04957767b0d"
@@ -1274,11 +1342,12 @@ dependencies = [
 "checksum dwmapi-sys 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "07c4c7cc7b396419bc0a4d90371d0cee16cb5053b53647d287c0b728000c41fe"
 "checksum either 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "740178ddf48b1a9e878e6d6509a1442a2d42fd2928aae8e7a6f8a36fb01981b3"
 "checksum enum_primitive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "be4551092f4d519593039259a9ed8daedf0da12e5109c5280338073eaeb81180"
-"checksum env_logger 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0561146661ae44c579e993456bc76d11ce1e0c7d745e57b2fa7146b6e49fa2ad"
+"checksum env_logger 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "afb070faf94c85d17d50ca44f6ad076bce18ae92f0037d350947240a36e9d42e"
 "checksum find_folder 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9f6d018fb95a0b59f854aed68ecd96ce2b80af7911b92b1fed3c4b1fa516b91b"
 "checksum fnv 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "2fad85553e09a6f881f739c29f0b00b0f01357c743266d478b68951ce23285f3"
 "checksum fps_counter 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e87181dcb1c9f3297845af26d5d78c4936ff12f8abe1c2a5507459d45f5236a6"
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@@ -1310,7 +1378,7 @@ dependencies = [
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@@ -1369,16 +1449,12 @@ dependencies = [
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@@ -1390,7 +1466,6 @@ dependencies = [
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diff --git a/Cargo.toml b/Cargo.toml
index fb52cc6..d1c1a91 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -39,4 +39,4 @@ rand = "0.4"
 fps_counter = { version = "1.0", optional = true }
 
 [dev-dependencies]
-quickcheck = "0.6"
+quickcheck = "0.8"