Support for Python 3

pycerberus supports Python 3 out of the box (tested with Python 3.4+) as well as Python 2.7. pycerberus 0.6 uses a unified source tree (pycerberus 0.5 relied on 2to3 and some custom hacks).

As far as I am aware the Python 3 version of pycerberus behaves exactly like the Python 2 version.