Add oauth_provider to Studio INSTALLED_APPS

cms/envs/common.py

@@ -1050,6 +1050,7 @@ INSTALLED_APPS = [
     # These are apps that aren't strictly needed by Studio, but are imported by
     # other apps that are.  Django 1.8 wants to have imported models supported
     # by installed apps.
+    'oauth_provider',
     'courseware',
     'survey',
     'lms.djangoapps.verify_student.apps.VerifyStudentConfig',