IBM.H is gone, video stuff re-organized. Keyboard stuff reorganized.
Machines that have their own video, mouse and/or keyboard now have all this in their machine file.
Fixed and other cleanups here and there.
The AT keyboard "write to mouse" command now returns 0xFF (error) when no PS/2 mouse is attached - fixes hangs on AOpen AP53, ASUS P/I-P55T2S, and Tyan Titan Pro/ATX when not using PS/2 mouse;
Fixed the emulation of the SMC FDC37C669 Super I/O chip - serial ports now work correctly on the AOpen AP53 and the ASUS P/I-P55T2S.