Merge release back to master

TE-2525 Finish removing nose.tools usage

Revert "Add feature to send an e-mail to staff when a student enrolls"

LEARNER-5989 Update eligible student record modes

EDUCATOR-2120 allow Community TA to see all discussion posts regardless of cohort and enrollment track

mattdrayer/ENT-1149: Bump edx-enterprise to 0.72.5

Include no-id-professional as an interesting mode to credentials

Fix pathway caching to work with multiple pages returned from endpoint

Further downgrade gunicorn.

18.0 seems to be doing a different thing with REMOTE_ADDR.

Putting this back to the last working version in production.

fixed flaky test from grading

Improve CourseEnrollment admin search presentation

EDUCATOR-2120 allow Community TA to see all discussion posts regardless of cohort and enrollment track

Downgrade `gunicorn` and run `make upgrade`

This reverts commit 370501d1.

There is a breaking change in gunicorn 19 which changes
the behavior of the `REMOTE_ADDR` request meta info. It
no longer correctly passes through the value of X-Forwarded-For
if that header is present.

This resulted in making anything that looked at this attribute
think that all requests were coming from 127.0.0.1

This broke the django-ratelimit-backend library which relies on
this feature to determine if a user has had too many login attempts.

Fixes unnecessary error reporting by screen reader

Removing student records waffle flag from LMS

This patch would inject error message dynamically for
screen readers only when there is an error state. In
normal flow screen reader would not be reporting any
errors to users.

LEARNER-5865

Recreate caches because we rolled back a migration that was added

Revert "Adding more logging"

ENT-1135 Upgrade edx-enterprise to 0.72.4

Add ModelAdmin for UserRetirementPartnerReportingStatus

Primarily, this was added for convenient bulk moving of processing
states from True to False without having to incur the round-trip
duration of a devops support ticket (in which they run SQL on our
behalf).

Move pin of `gunicorn` to 2015 and run `make upgrade`

Adding more logging

exempt pdf view from xframe_options:deny

add course level mobile app exclusion for vop and cgv3 experiments

Gunicorn Change Log: http://docs.gunicorn.org/en/stable/2015-news.html