Flesh out jackcompiler.compiler subpackage.

10_11_jack_compiler/jackcompiler/compiler/__init__.py
	-Add content to `compile_cst()`; still a WIP.

10_11_jack_compiler/jackcompiler/compiler/vmwriter.py
	-Add a `vmwriter` module, with a partly implemented `VMWriter`
	class, which'll abstract away raw virtual machine code.