The admin site models and URLs were unable to be accessed during Unit Tests.

This meant that if a test attempted to access an admin model page, the 

page would respond with a 404 error.
Adding django.contrib.admin.autodiscover() during initial test setup 

loads all the admin UI models, so tests have access to admin URLS.
DefaultReviewer form tests, WebhookTargetAdmin form tests, and OauthAdmin 

form tests were all added as well, to check that forms function as 

expected.

Running ./tests/runtests.py returns no errors. The form tests added

pass.