added corrections to how alphanumeric text is actually stored in video
RAM. added corrections to how odd/even mode and odd/even memory write
mode (two different bits in sequencer and graphics controller) apply to
writing alphanumeric text. fixed code in INT 10h font loading code to
set the odd/even disable bit properly. Fixed INT 10h modesetting code
NOT to set odd/even disable for alphanumeric text mode (as real hardware
does). So far, these fixes are 80% towards my goal of fixing the
mis-emulation responsible for Windows 95's boot logo improperly
loading/saving alphanumeric video RAM in DOSBox.