Add comment endorsement to discussion API

certificates event tracking SOL-886

Create a common paginated list view

Fix bug in discussion API comment update

TNL-2384

Refactored Studio's PagingView to use RequireJS Text and moved it
to common so that it can also be used by LMS.

Deprecate course details API v0

This bug caused any attempt to update a comment with a non-null
parent_id to result in a 500 error without applying the update. The bug
was introduced in commit 2c7590d1.

A version of #8260 that is consistent on jenkins and locally

Fix dark lang and django.middleware.locale behaviors LOC-72 LOC-85

Reduce the number of queries when walking parents in MongoModuleStore by avoiding cache misses on the data due to missing runs

some optimisations

refactored code and added created event

added test to make sure generate event is emitted

changes based on feedback on 6/11

added certificate web page and tests

fixed quality violations

(SOL-835) Addressing flakiness of the reindexing bokchoy acceptance test

Add feature flag to allow hiding the discussion tab for individual courses.

Only return languages we've actually released LOC-85
Perform fuzzy matching to greedily serve the best released language LOC-72

Add to dark_lang middleware

Merge release into master

Conflicts:
	cms/djangoapps/contentstore/views/course.py

MIT CCX: Use CCX Keys

Prevent duplication of tabs with different names.

Make addCleanup idempotent.

Update translations (autogenerated message)

only require ccx-keys once

get_current_ccx will now expect a CourseKey instance as its argument, and will raise a value error if this expectation is not met.

document reason for local import

add special methods to pass attribute setting and deletion through to the wrapped modulestore

add __setattr__ and __delattr__ per code review, update __init__ to work with new methods

style change per code review

clean up context manager usage as recommended by code review

remove unused code and imports

convert modulestore type tests to use the `get_modulestore_type` api, remove unused imports

code quality: add docstrings

increase coverage for utils tests

fix bug found in testing.

increase test coverage on modulestore wrapper

code quality fixes

code-quality: ignore import error, but mark site for future consideration