Fixed dumb bug.
Implemented importStar.
Improved canvas modal. (This may actually be removed in the future.)
Exported a couple more exceptions that I needed.
Exported the useful makeGenerator function.
Began implementing some caching to improve the performance of function calls.
Added a function that can be called from JS modules that raises a TypeError if a method is called with the wrong number of arguments.
Minor improvements to the image module.
Initial (rough) check-in of the media module, based on Guzdial's media computation API.