Document 'token' API with TSDoc.

[digisomni]

https://github.com/vircadia/Iamus/blob/master/docs/API-Tokens.md

Document this API within the code and try to ferry as much relevant information in.

[Misterblue]

not sure what this is requesting. Is the issue that the code doesn't have enough comments to make the token interactions clear?

[digisomni]

Ah, I should open more issues but in essence I wanted to split up the tasks of documenting the APIs with inline comments into multiple pieces so it doesn't seem like some insurmountable task. Documenting each API is a good start.

In-code comments are best for things like this so changes are more likely to be reflected in documentation.