Add super() calls to setUp/tearDown that are missing them

Also, I replaced a number of tearDown methods with addCleanup instead.
And also remove some unneeded patch.stopall() calls.

common/djangoapps/monkey_patch/tests/test_django_utils_translation.py

@@ -78,6 +78,7 @@ class MonkeyPatchTest(TestCase):
         """
         Remember the current state, then reset
         """
+        super(MonkeyPatchTest, self).setUp()
         self.was_patched = unpatch()
         self.unpatch_all()
         self.addCleanup(self.cleanup)