+ Convert setup.py test to run py.test instead of tox
+ Tox should now run setup.py test
+ TravisCI will create a job for each TOX_ENV and then execute
tox to run the tests for that TOX_ENV
+ As we use Tox there's no need to run seperate builds for
python3.3 and python3.4
+ There's no need to install the requirements in main
environment as all dependencies are handled in the Tox
virtualenv's