Python 3.*/Django 1.5+ support. 

1. Python 3.*/Django 1.5+ support. 
2. Avoid new redis connection on each request, its very useful on services like heroku with limited redis connections
3. Tests moved outside ``redis_sessions`` package
4. Small pep8 fixes
5. Refactored ``getattr`` 
6. Bump version
7. travis-ci build , tests passed Python 2.5, 2.6, 2,7, 3.2, 3.3 and pypy