Upgrading the Checkmate Amiga 1200! Indivision AGA, PCMCIA etc

Adding all kinds of stuff to the LGR Commodore A1200 build! Indivision AGA MK2cr, PCMCIA Compact Flash, 15-pin PC joystick support, swapping the mouse ball for laser, upgrading the Kickstart ROM, along with plenty of little tweaks and fixes.