Remove debugging artifacts
Rename move_to to process_move and put it near process_byte
Move ctrl_1b before ctrl_1c
Remove intermediate jump to put_scrcode
Move putscr_then_done to remove another intermediate jump
Rename putscr_then_done to put_scrcode
Move put_char and scrollup out of the middle of the control code handlers
Move cursor state into init_scrn
Move keyboard location inits together
Remove BIT fall-through trick to improve readability
Decouple cursor right and linefeed routines