Merge pull request #8403 from edx/sarina/remove-redefine-django14-cors

cms/djangoapps/contentstore/views/assets.py

cms/djangoapps/contentstore/views/certificates.py

cms/djangoapps/contentstore/views/checklist.py

cms/djangoapps/contentstore/views/course.py

cms/djangoapps/contentstore/views/entrance_exam.py

cms/djangoapps/contentstore/views/export_git.py

cms/djangoapps/contentstore/views/import_export.py

cms/djangoapps/contentstore/views/library.py

cms/djangoapps/contentstore/views/public.py

cms/djangoapps/contentstore/views/tabs.py

cms/djangoapps/contentstore/views/user.py

common/djangoapps/django_future/__init__.py

common/djangoapps/django_future/csrf.py

common/djangoapps/external_auth/views.py

common/djangoapps/student/views.py

common/djangoapps/track/views/__init__.py

common/djangoapps/track/views/segmentio.py

lms/djangoapps/branding/views.py

lms/djangoapps/ccx/views.py

lms/djangoapps/courseware/views.py