* action() returns void - this gets rid of checks in vt_from_slave()
* split up ACTION_PRINT into ACTION_PRINT (ASCII) and ACTION_UTF8_PRINT
ACTION_PRINT is on the hot path, and we want it streamlined.
* Remove run-time checkout for unimplemented state transitions, as we
shouldn't have any of those left.
* Don't re-load current VT state on each iteration in vt_from_slave()