s/django.core.urlresolvers/django.urls/g

Django 1.10 deprecation fix for Hackathon XIX
Addresses PLAT-1397

lms/djangoapps/instructor/tests/test_registration_codes.py

@@ -3,7 +3,7 @@ Test for the registration code status information.
 """
 import json
 
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.test.utils import override_settings
 from django.utils.translation import ugettext as _
 from nose.plugins.attrib import attr