Fixed IDE and ATAPI 8-bit data reads and writes by rewriting the IDE and CD-ROM PIO data read and write code so that the base code is now 8-bit;
Added some compiler directives that if set, will enable togglable logging and log breakpoints;
Empty IDE channels now always report a status of 0x10 rather than 0x20, and do it on port 3F6h/376h/36Eh/3EEh too, fixes OAKCDROM.SYS infinite loop when hitting an empty IDE channel.
Four CD-ROM drives are now emulated;
ATAPI DMA is now emulated;
Unified CD-ROM pass through to host drive handling;
Applied all (applicable) mainline PCem commits.