Python REPL: exit when the user types exit

This is a great study in tech debt, bad attitudes and work arounds.

That said, I think this will be a great benefit to python, I often end up mistyping only to curse at the stupid computer that knows exactly what i ment yet, does not do it. I'm sure it's going to be a good fit for python4, and that it'll help students when adoption rolls around in 10-15 years.

This bug report is at risk of turning into a bike shed flamewar and I don't think it needs more attention from the masses. Please don't upvote.

:q

:q!

ctrl-C

(turns off computer)