Sped up the staticfiles_tests by allowing them to only search a few relevant...

Sped up the staticfiles_tests by allowing them to only search a few relevant directories, rather than every single test application.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14396 bcc190cf-cafb-0310-a4f2-bffc1f526a37