Py3k support

Hi Carl, I'm here at the pycon sprints working on porting projects to python 3. This seems like a good candidate since we use it in our django apps at work. I managed to get all the tests passing in both python 2.7 and 3.3 and you've got really great test coverage, so it should be ready to go, I think.
Let me know if you can think of anything else needed, or if you don't like any of my changes.
Thanks.