Fixes to various hard disk controllers;
Added the Packard Bell PB640;
Fixed the InPort mouse emulation - now it works correctly on Windows NT 3.1;
Removed the status window and the associated variables;
Completely removed the Green B 486 machine;
Fixed the MDSI Genius;
Fixed the single-sided 5.25" floppy drive;
Ported a CPU-related commit from VARCem.
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.
Fixed the Force 4:3, Enable EGA/(S)VGA overscan, and Scale options;
Fixed a bug regarding register 0 of the SMC FDC37C665 Super I/O chip;
Commented out some excess logging.
The Settings dialog now correctly filters devices by bus;
Split the dual VLB/PCI graphics cards into VLB and PCI versions;
Device filtering is now done using the new device_is_valid() call that compares device flags to machine flags;
Moved the NCR-based SCSI controllers to the main branch;
Moved the NE1000 to the dev branch until it's finished.
