Experiment for type casting.

Didn't go especially well. Couldn't get implicit type casts to work,
they seem to require abstracts. Couldn't figure out how to verify at runtime
that the type cast is actually correct (ie this thing I'm casting *really is*
what I'm casting it to. Thus it allows casting of a symbol into a string
Experiment: Calling Haxe from Js
Found a better way to call haxe from js
First pass at compiling and calling from js
Compiling interpreter into frontend dir
Can execute the interpreter in the browser