TE-2524 Stop using nose.plugins - LMS 2

mroytman/course validation default grading policy

Render credit pathways in program details sidebar

pass target branch to paver

Revert "fix poster display issue with hls"

Update edx-drf-extensions to 1.5.5

This reverts commit b9ebe5ea686fc1b16fccd0f276fbc1d53a5c3468.

Exempt xblock renderer from xframe options deny.

Fix discussion blackout date pasrsing.

LEARNER-6002

removed lettuce test points for discussion component

bokchoy tests for textbook page

`Make Upgrade` + Update Django to latest patch version.

There are issues in the newest version that we don't want to pick up yet.

Add better http error handling to award program certificate

Upgrade Django to 1.11.15 in base.in as well

Update gunicorn slightly.

TE-2524 Stop using nose.plugins - LMS 1

We're quite far behind, let's start by just looking at the treadmill.

Upgrade Django to 1.11.15

Add credit pathway caching

Add user id to partner reports

Gate access to the CourseEnrollmentAdmin view with a waffle switch

Properly handle errors in award program certificates

LEARNER-6004

discussion component bokchoy tests