wip
move rk methods onto struct
Refactor rk05
Fix console
wip
Introduce unibus
Merge branch 'rk05-refactor' into unibus-rk05

Conflicts:
	pdp11.go
	pdp11_test.go
	rk05.go
Merge branch 'rk05-refactor' into rk05-step

Conflicts:
	pdp11.go
	pdp11_test.go
	rk05.go
wip
RK05 now steps independently
Merge branch 'master' into unibus-rk05

Conflicts:
	pdp11.go
rk now lives on unibus
wip
wip
Merge branch 'kb11-fixes'

Conflicts:
	pdp11.go
There is a very interesting bug here.

If the console is too fast, then it can crash the cpu. Artificially slowing
down the console makes the emulator a lot happier
Cleanup terminal

./console is broken, but the input tests pass