Python 3: Use six.moves for moved imports
Python 3: Differentiate byte and unicode strings

All data having to do with HTTP requests and responses is generally a
byte string and now marked as such. See
https://docs.djangoproject.com/en/dev/topics/python3/#httprequest-and-httpresponse-objects

Classes with a __unicode__ representation have been updated to use the
python_2_compatible_unicode decorator.
Python 3: items() now returns an iterator

This fix is necessary as without it, Python 3 complains about locals()
changing size when the key variable is assigned for iteration.
Run test suite against Python 3
Bump version to 0.8.3
Append #egg= to requirements

This was required in django-oscar-paypal, and is a good practice
whenever installing a requirement via an URL instead of a package name.