X68000

DMA fix.

Add Keyboard Layouts (by Puu-san) to use special keys of X68000 keyboard (HELP, 登録 "Touroku", XF3, etc...) (Marc Roy).

Midi fixes (Rebel40 and Puu-san) (Marc Roy).

Add controllers - Turbo 2-button, MegaDrive 3-button, Capcom 6-button, and rough in XE-1AP back-end (David Shadoff).

changes to relax sdram to 80 mhz and fixes (albconde).

Fix YM3802 MIDI timing and TX FIFO behavior (odiaboeeu).

Updated framework.