Fix broken tests

* Django >= 1.5.1 requires SECRET_KEY setting to not be an empty
  string
* Remove html tag from table actions rendering to make test more
  robust

Change-Id: I584db530dd6272cda42ba4dfc2edbe9c1902f55d
Signed-off-by: Rosario Di Somma <rosario.disomma@dreamhost.com>