+ Refactor ast.c and give each operation its own proc, i.e. instead of huge
node_type switches call a corresponding procedure. Should help with debugging,
stack traces etc.

+ Add const and volatile attributes to types

+ Add const to procedures

+ Add external to procedures, essentially disables templates and name mangling,
to be used to interface with C

+ Come up with some better file extension, .cu seems to be used by cuda
	- In fact Copper is already taken :(