Used a django.test.TestCase for compatibility with @override_settings.

These tests were silently skipped.

tests/regressiontests/templates/tests.py

@@ -23,7 +23,7 @@
 from django.core import urlresolvers
 from django.template import loader
 from django.template.loaders import app_directories, filesystem, cached
-from django.test import RequestFactory
+from django.test import RequestFactory, TestCase
 from django.test.utils import (setup_test_template_loader,
     restore_template_loaders, override_settings)
 from django.utils import unittest
@@ -156,7 +156,7 @@ def __str__(self):
         return 'ŠĐĆŽćžšđ'
 
 @override_settings(MEDIA_URL="/media/", STATIC_URL="/static/")
-class Templates(unittest.TestCase):
+class Templates(TestCase):
 
     def test_loaders_security(self):
         ad_loader = app_directories.Loader()