July 2012: v2.0 
	- Initial release

July 2012: v2.0.1 
	- fixed bug so ATR images are read correctly

July 2012: v2.0.2 
	- fixed bug so keyboard works in any locality

Aug 2012: v2.1
	- improvements to video timing
	- corrected calculations for DMA cycle stealing 
	- ATR header written for disk images with extensions .ATR or .atr
	- joypad buttons added for OPTION, SELECT, PAUSE and START
	- improvements to 5200 joystick
	- 5200 keys 0..9 now also at numeric keypad
	- 6502 fixes
	- PRIOR bit5 fixed for overlapping players
	- NMI fixes
	- Trace output better formatted and more accurate info
	- Tools menu added (disable PMGs, DLIs, etc.)
	