Roughly implemented the SCSI IDENTIFY message LUN operation, fixes some SCSI controller drivers in some situations;
Added an undocumented CMD640 IDE controller register required by Linux and by a DOS driver.
- 86Box's own headers go to /86box
- munt's public interface goes to /mt32emu
- all slirp headers go to /slirp (might want to consider using only its public inteface)
- single file headers from other projects go in include root