Created Articles Model

- Added unittests and separated it into folders.
- Updated the settings.py file to plugin to the database.
- Did south migrations to the database (migration file 0006 might be
wonky as I had to edit by hand, worked for forward don't know about
backwards).

Issues
------------
- The tests are very slow possibly due to raven not being configured and
celery being loaded to the database, tried to implement following link
but wasn't helpful
http://stackoverflow.com/questions/4055860/unit-testing-with-django-celery