Initial naive try to check for Python 3.3. support.
Implement only change suggested by 2to3.
Python 3 compatibility: Ensure check_output returns a string, not a bytes obect.
Python 3 compatibility: `OSError` became `FileNotFoundError`. 
This supports both variants (and the errno is the essential info, anyway)
Add working setup for tox (http://tox.readthedocs.org/en/latest/)
Make Travis use tox.
Remove deprecated --use-mirrors flag. Don't install test deps, as tox does this anyway.
Bump version to 1.1.