GeoChess v1.3

Fixes:

• 128 mode 80 column screen is working now.
• no more visual artifacts
• C64 doesnt display 40/80 menu
• Switching 40/80 in 128 mode works properly
• code cleanup

Known defects:

• Still need to address the sprites
• Castling
• Pawn promotion
• En passant

GeoChess v1.2

• Fixes bug allowing some pieces to incorrectly jump over others.
• Improved C128 80 column support