Testbeds for various graphics modes

+3d_glasses
	some attempts at getting anaglyph 3d (3d graphics) working
	on Apple II.  Didn't work

+ dgr
	code for testing double lores

+ dhgr
	code testing out double-hires

+ dgr_viewer
	a double-lores image viewer

+ galaxy
	an implementation of a galaxy algorithm that looked cool
	fantastically slow on Apple II

+ gr
	code for testing lores

+ gr_viewer
	a lo-res image viewer

+ hgr
	code for testing hires

+ hgr_viewer
	a hi-res image viewer