Add .db files to gitignore
Disable django-auth-ldap logging in testing environment
Switch to the django messages framework

In order to adjust the unit tests properly, I had to create a custom
TestCase class with three new assert functions to cover testing of the
messages. The custom class is taken from this link:
http://stackoverflow.com/questions/2897609/how-can-i-unit-test-django-messages
Move OkupyTestCase to common
Merge branch 'master' into signup_tests
Fail the message tests (or set expected count 0) when there are no messages
more wip