Applied all applicable PCem commits;
The PS/1 and PS/2 machines now have the correct graphics cards - fixes the reference diskettes;
The open dialog code now changes directory to usr_path after the dialog is closed;
Disabled excess logging in the TI SVGA code.
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.