Major commit, cleaning a lot of old stuff.

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.

src/sound/midi.c

@@ -4,7 +4,6 @@
 #include <stdlib.h>
 #include <wchar.h>
 #include "../86box.h"
-#include "../ibm.h"
 #include "../device.h"
 #include "../plat.h"
 #include "../plat_midi.h"