Also run it across the whole tree to get everything using the One True Style.
We don't yet run this in an automated fashion as it's a little slow, but
there is a snippet to do so in makeall.sh.
Move the bulk of exec() into a new pump(). Since SDL wants to drive the
event loop itself, this is a requirement. We also add a WaitMode flag to
allow for immediately pumping events -- again, this is required because
SDL wants to be in full control of the event loop, and not let us wait.
