* Added sound master control registers to mmio_addresses.
* Merge FifioEnable into SoundStatus, reduce struct sizes.
* Rename SOUND_CHANNEL_CTL to something a bit simpler.
* .
* more updates, much more to do soon.
* hello world works again.
* fix key interrupts.
* remove the old book
* don't forget timers.
* we can just use search, duh.
* cleanup
* more bios
* finished most mmio, finished bios.
* dump some old macros that shouldn't have been pub to begin with.
* Update README.md
* for now, just make this a u16
* timers
* fix hello_world
* timer fix
* docs on timers
* block resetting work ram for now.
* put preserves_flags on bios calls as appropriate
* add a code page 437 tile sheet.
* docs.
* sound :( it's all bad but we'll fix it in 0.5
* move most backup files back into the lib.
* CI might work now?
* fix up non-serial examples.
* oops, gotta check out the repo.
* readme.
