Major cleanup to code, set_interrupt() now only looks at 3 lower bits
to determine interrupt level. Some Copyright notices have been updated.
DC10 now handles modem control correctly. And will support up to 32 lines.
Modem lines start at a fixed value and follow the data lines.
Update the RP10 disk controller to handle multiple access and
to properly handle status on a per drive basis. Also added in
start of proper debuging functions. Change CPU to not miss
interrupts when multiple interrupts occur.
