Enable deletion of coaches and students.
Merge branch 'release-0.12.0' into delete_user
skip js catalog tests on travis
Merge pull request #2105 from learningequality/central-develop-merge

Central develop merge
For #2034 - "Knowledge map can't be scrolled" - this is the initial fix to allow user to scroll horizontally if the contents of the map is more than its container's width.
Remove codes to set the `overflow` CSS attribute of the map container and set it's value to `auto`.
use url reverse lookups for client side requests
Merge pull request #2109 from aronasorman/1955

use url reverse lookups for client side requests
Update ReadMe to reflect transition to GH wiki.
Add `FacilityGroup.description` field.
Modify the templates to add it with the group name for the hover text of the group link like manage and coach group.
Merge branch 'release-0.12.0' into delete_user
SECURESYNC CHANGE:
Change soft delete method to soft_delete rather than delete.
Call soft_delete instead of delete on related models.
SECURESYNC
Add custom queryset to SyncedModelManager to allow for soft_delete method on queryset.
SECURESYNC
Make soft_delete try to soft_delete related models, but fall back to full deletion.
Change facility management deletion operations to .soft_delete
SECURESYNC
Documentation of all_objects SyncedModel property.
Fix user creation form to enforce username uniqueness across active and deleted users.
Add custom soft_delete override on FacilityGroup model.
Prevent deletion of soft-wrapped items.
Refactor facility tests to put FacilityTestCase in base.py for import.
Tests for soft_deletion of facility objects.