Missing ValueRef Features

[zicklag]

Here are some things we need to figure out how to expose to JavaScript on JsValueRefs. Creating a list so I don't forget.

• Indexing into maps
• Insert/Remove items from lists
• Equality Checks: Various Updates For Game Integration #23
  • Update types, currently TypeScript doesn't know about the .eq() method.
• Cloning
• Hashing ( Not sure if it's that useful, but since it's in the reflect trait we might as well support it. )
• Option/null handling. For instance, it's hard/impossible to check if an Option<Entity> is None.

[jakobhellermann]

• creating new values
• dealing with enums

[jakobhellermann]

I'm ticking off "creating new values" because Value.create(Type) now exists.