This would be useful, for example, to allow the assembler to write
straight to an AT28 EEPROM without going to RAM. This would be a
life saver in machines with tight RAM such as the SMS.
With KEY and EMIT being switch words, most of the high layer can
be defined before drivers.
In addition to this change, I've compacted core blocks which were
becoming quite sparse.
This duplicated feature existed because of bootstrapping issues
with LIT", but again, with careful threading, we can clean things
up.
We can now have a proper "Collapse OS" prompt :)
