Meaningful output on exception

[daylanKifky]

Would it be possible to get a backtrace or something when an exception is raised from some of the handlers? At the moment the server just closes the connection silently. Perhaps just as an optional debugging flag?

[SupraSummus]

simple workaround:

import logging

def handleMessage(self):
    try:
        do_things()

    except:
        logging.exception('error during handling user data')
        self.close(status=1011, reason='Internal server error')

[dpallot]

Seams reasonable to me, ill look at it.

[benjamingorman]

Any progress on this? @dpallot Might you accept a PR to implement this? It took me a while to realize that the library was silently discarding exceptions from the handlers - this really shouldn't be the default behaviour.