Convert repo to TypeScript

[zepumph]

I'm surprised to still see so much in JavaScript over here in dot. I ran into this with Bounds3, and will convert it as I butt up against it over in phetsims/density-buoyancy-common#98

[zepumph]

[zepumph]

It looks like there was a bug in Bounds3.transform. The jsdoc said that it wanted a Matrix4, but the implementation seems dependent on Matrix3. I added TODOs pointing to this issue. @jonathanolson can you help out with this? I don't see Matrix4.isIdentity().

dot/js/Bounds3.ts

Line 872 in 8a8ed84

* // TODO: should be Matrix4 type, https://github.com/phetsims/dot/issues/125

[jonathanolson]

It should eventually support Matrix3 (just a rotation) or Matrix4 (rotation + translation).

[samreid]

I'll work on converting Complex.js to TypeScript.

[samreid]

I'll work on Random.js next.