This emulator provides a rough way for binaries designed for this CPU to be
executed in a virtual/emulated CPU for testing purposes. This patch also adds
a small test setup for automated assembly, execution and checking of register
postconditions for programs.

These tools are currently fairly useless for real-world programming. Each of
them takes in either asm or binary, translates this to the internal intermediate
representation of a list of instruction structs, and then translates and outputs
in the same format that they took it in. These are mostly oly useful for testing
purposes, but may one day be useful if e.g. an optimiser stage is put in between
the input and output stages.

I'm going to regret this

This refactors the disassembler into two stages with the list of struct
instruction (currently also output by the parse stage) as an "intermediate
language" between disassembly and assembler output. This should make these
units, especially the "machine code => IL" section, more reusable for future
soft emulation work.