Handle PEP 475 fallout.

Closes #255

As of Python 3.5, PEP 475 gets in our way.  Runners with long time.sleep()'s
in their _snooze() method (e.g. the retry runner) will have their system call
implemented time.sleep() automatically retried at the C layer.  The only
reliable way to prevent this is to raise an exception in the signal handler.
The standard run() method automatically suppresses this exception, meaning,
it's caught and ignored, but effectively breaks the run() loop, which is just
what we want.

The lmtp and rest runners implement their own run loops, so they also have to
handle this exception, by ignoring it.

0 files changed, 0 insertions, 0 deletions