Cherrypick hotfix-2015-07-07 into release candidate

Includes the changes from 897fddba3e.
Those changes were introduced while resolving a merge
conflict from release back into master.

common/djangoapps/student/tests/test_credit.py

@@ -6,6 +6,7 @@ import datetime
 
 from mock import patch
 import pytz
+from mock import patch
 
 from django.conf import settings
 from django.core.urlresolvers import reverse