Clear caches between tests for ModuleStoreTestCase/SharedModuleStoreTestCase

Make ensure_indexes mgmt cmd semi-idempotent.

MA-1918 returning None for courses with no handouts

Query counts already happen at the model and Python API test layers.
Having query counts in the HTTP API tests makes things more brittle
because that includes middleware that this code should not be aware
of. We don't want to have to revisit these tests every time
another piece of middleware is added or removed.

Remove flaky decorator from test_cancel_comment_edit

Cached values were leaking across tests, causing difficult to debug errors,
particularly when using Config Models. As part of this work, certain tests
that had query counts that relied on those values being cached needed to
be adjusted up.

Test passed over 100 times in Jenkins.
TNL-4057

indexes with different options. Emit warning instead and continue.

Implement celery task to award program certs.

ECOM-3354

Fix up the excluded extensions bit.

This adds the missing admin class, and registration of it, required to
actually change the value of the excluded extensions configuration.

Bump ORA version to 0.2.7.

Get tests running successfully on CircleCI

Other small changes:
* output the list of installed python packages
* tee the pylint output to the console so the build doesn't timeout when computing violations

Move markup helpers to djangolib

Move JSON samples out of translated strings so translators can't make mistakes

Don't use using() in migrations

Correctly set certificate status for audit certs when regenerating.

Bump hash for problem builder

COR-2403

Upgrade Django from 1.8.7 to 1.8.9

Update translations (autogenerated message)

Correctly format date block dates.

Remove unused MULTIPLE_ENROLLMENT_ROLES feature setting

bookmark button js caching

LMS: darkening a gray on the profile page