Feature/autodeploy testing

Updates to allow ab_testing project to be deployed via ansible/Jenkins in AWS.  Some changes:
- give project urls consistent and unique prefix of 'ab-testing/'
- add console and file logging to test/qa settings files
- add gunicorn and redis as requirements in relevant environments
- update static url and file finder
- move secure_proxy_ssl_header setting to base settings
- update supervisor.conf.j2 template to use djang_settings variable
In the TLT django projects `test` corresponds to the integration environment on http://test.tlt.harvard.edu.  We've generally created a `test_settings` file for running unit tests.  I know it's confusing, but we're going through a process of changing names for our environments so over the next month the name `test` should be freed up for running of unit tests.  In the meantime, for this project to fit in with the other deployable projects in our Jenkins job we'll need to borrow `test`.