Fixed bug where classes would not typecheck all declarations.
Refactored JS codegeneration components into the wyvern.targets.JavaScript namespace
Introduced tuples, both as types and as method arguments.
Introduced JSObjectType, allows JS objects to be interacted with without static typing. Note that this defers containment checking to runtime.

Added tests for all new functionality.
Merge branch 'master' of github.com:wyvernlang/wyvern