Update readline bug comment
Update readline bug comment

Add a TODO to add a version check after 5.6.7 ships.
lvht/psysh,damiankloip/psysh,adetch/psysh,damiankloip/psysh,mubassirhayat/psysh,bobthecow/psysh,adetch/psysh,bobthecow/psysh,lvht/psysh,damiankloip/psysh,mubassirhayat/psysh