add io_irq and io_nmi LEDs
clean up CIA test bench output to reduce verbosity.
fix CIA test for ISR clearing after read.
fix keymapping for delete key.
delete unused port.
make CIA ports default to $00 instead of $FF so that keyboard works on
boot, even with CIA read bug.
remove port to keymapper that has been deprecated
reduce verbosity of s command.
fix BRK instruction to actually set B flag when pushing P.