added the plumbing and serialization for the additional palette colors and the XO-chip enable flag.
added color support in the sprite editor
fixing some mistakes in cropping/extending the sprite editor image.
audio should stop if a new pattern begins playing before an old one completes
initial checkin of XO-Chip implementation. I still need to do quite a bit of testing.
added prettyprinting for the new instructions
retrofitting the decompiler to support the new XO-Chip instructions. Banked memory poses some problems for disassembly since label references can now be ambiguous or at least context dependent. I think I'll just have to provide a best-effort approach and accept that labels will not be extracted perfectly.
avoiding the generation of illegal instructions by being a bit more selective decompiling bank and plane instructions.