Merged User And Anon Quiz Attempts
Refactored code depending on Anon and User Quiz Attempts.
There's now one place to get unique_user_key for both logged in and anon users.
Redis client is created only through redis_cache.get_redis_connection
Testing is now done in alternate redis instance running at 6380

http://chrislaskey.com/blog/342/running-multiple-redis-instances-on-the-same-server/