Merged floppy.c and fdd.c and renamed floppy_*.c (the floppy image format handlers) to fdd_*.c;
Reading the AT or PS/2 keyboard controller status no longer clears the transmit timeout bit, fixes error 8601 (mouse error) on the IBM PS/2 Model 80;
MMU translate and DMA physical reads and writes now go through _mem_exec instead of directly to ram[], should fix the last remaining problems with remapped mappings;
Implemented the Sound gain dialog;
Added the resource for the "New floppy image" dialog and the needed functions for the functionality of exporting the currently mounted floppy image as 86F, both of which should be finished in the next commit;
Applied the CD-ROM fixes from the PCem commit;
Added the "Keep ratio" option for full screen stretch.
Re-worked the system pathnames (pc.c), renamed cfg_path to usr_path.
Other small things here and there.
Logitech bus mouse re-worked, should be OK now.
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 (hopefully) pass through in the Windows CD-ROM IOCtl code;
Fixed the legacy I/O address handling on the BT-958D, now it behaves correctly - legacy I/O address disabled by default, can be enabled in AutoSCSI (removed the setting from the device config struct);
The BT-958D PCI-configured I/O space now correctly gets 32 ports and not 4.
Two-phases SCSI disk write direction commands (needed for the NCR5380);
Renamed cdrom_ioctl.c/h to win_cdrom_ioctl.c/h and moved them to win/;
Moved some CD-ROM and floppy initialization blocks to the appropriate files.
