various utilities/ programs involving Apple II sound/music

+ bgmusic
	play music in the background while running basic programs
	used in my appleiibot demo

+ cd
	a pt3 file ready for a demo

+ chiptune_debug
	code trying to debug issues with chiptune player

+ chiptune_player
	original ym chiptune player

+ dya
	6-channel ym player, for some of DYA's music

+ electric_duet
	some experiments with Paul Lutus's electric duet 2-channel
	speaker music

+ ksp_theme
	some initial tests of various ways to access the mockingboard
	plays the Kerbal Space Program theme with some images

+ megamusic
	code for playing mockingboard music while in vapor-lock/cycle-count
	mode

+ polly
	trying to reverse the sound effect code from the Pollywog game

+ pt3_lib
	pt3 vortextracker music player library for use in other code

+ pt3_player
	pt3 AY-3-8910 vortextracker player for Apple II / 6502

+ sound_effects
	some attempts at sound effects

+ still_alive
	mockingboard "Still Alive" ending to portal