cprint and cfprint text mode routines

[SMcNeill]

Remember, for speed, you can turn $CHECKING:OFF with mem to see a noticeable speed boost.

$CHECKING:OFF
_MemPut o, o.OFFSET + ts + (cx - 1) * 2, v As _UNSIGNED _BYTE
_MemPut o, o.OFFSET + ts + (cx - 1) * 2 + 1, c As _UNSIGNED _BYTE
$CHECKING:ON