Add support for -D_DEBUG to turn on debugging in syborg_stem_rom.oby, and remove debug_stem_rom.oby
This is "sensible debugging", selected by using DEBUG_DIR instead of BUILD_DIR in the oby file - as per the ancient buildrom conventions.
Assorted Hacks
1. syborg_keyboard.cpp
Replace sf\adaptation\qemu\baseport\syborg\keyboard\syborg_keymap.cpp with this file
and rebuild the baseport, to turn F10 into the Key of Death.
Pressing F10 will cause Kern::Fault("KeyOfDeath", 0x0f100f10), which will drop
you into the kernel crash debugger if you are using a UDEB version of ekern.exe