Fixed testing, fixed python3 compatibility, added classifiers for PyPI

- Made it possible to run `python manage.py test` and get passing tests
- Added a `.travis.yml` file to enable Travis CI builds
- Fixed Python 3 compatibility without compromising Django 1.4 compatibility
- Added trove classifiers to `setup.py` for PyPI
It is difficult to read though.  I only did it this way because I had seen it done that way in other projects; if there's a more readable alternative, I don't mind changing it.  I'm relatively new to Travis.