Fixed several bugs in TD0 and IMD loading;
Added FDC READ DELETED DATA, WRITE DELETED DATA, and VERIFY commands;
Mismatching data address marks are now handled correctly.
Improved TeleDisk support;
Added support for ImageDisk (IMD) images;
Added MSR registers 186 and 570 for the Intel i686 CPU's;
Applied both mainline PCem commits.
Fixed side flags when loading of double density TD0's created using a high density 5.25" drive;
GAP3 length for TD0 teacks is now calculated rather then fixed when it can not be reliably determined from data rate, sector size, and sectors per track.