Use unicode literals
Replaced dict.iteritems() with dict.items() as iteritems is not supported in Python 3
Use six.add_metaclass when adding metaclasses for Python3 compatibility
Replace __unicode__ with  __str__ method in test models
add tox testing infrastructure
fix test to work on python 2.6
Merge branch 'python3' of https://github.com/kaedroho/django-modelcluster into kaedroho-python3
add 'six' as a dependency
add python 3.2 and 3.3 to tox tests