fixes: ADMIN-2539
this moves and loads feature flags from yaml files. there should be
absolutely no changes to functionality of anything in the system.
Test-Plan:
change things with feature flags and different feature options, and make
sure they work the same way as before.
Change-Id: Id096e6c9975f86224c1ee07304cef79a0d4c7755
Reviewed-on: https://gerrit.instructure.com/187804
Reviewed-by: Carl Kibler <ckibler@instructure.com>
Tested-by: Jenkins
QA-Review: Jeremy Stanley <jeremy@instructure.com>
Product-Review: Rex Fleischer <rfleischer@instructure.com>