Support firefox 59 upgrade for CI and local testing

Disable course enrollments admin page OPS-2943

Remove test_video_player_a11y test

Define xss-linter rules on linter classes

Add search for courses API to allow building a mobile native search view

add entitlement creation and reissue to support

Remove tests that are flaky with firefox 59

add missing maintenance banner settings

Learner-3925

Use updated packages to avoid installing unwanted stuff

Include created datetime in entitlement support detail serializer

Upgrading edx-enterprise to 0.66.1.

https://github.com/edx/edx-enterprise/compare/0.66.0...0.66.1

Delete some unused settings

Move support actions to existing entitlement api

Initially introduced here:
  https://github.com/edx/edx-platform/commit/e0aa8cf78a1dc342ed4e00082768fb0a400a585f#diff-8a23909bc8d201fba8525b1dd6396247

Rendered irrelevant here:
  https://github.com/edx/configuration/commit/ece0ea00e9aacb1c1243b65fc1c16c7e7d815b23

Footer Design Implementation without using bootstrap WIP

Remove tests that fail on firefox 59