Merge pull request #1726 from cpennington/hotfix-fix-OEE-ajax-url

Fix LMS-1493
Allow colons in Locator fields.
Merge pull request #1742 from edx/ned/cherry-pick-pr-1740

Ned/cherry pick pr 1740
Add release notes for 061a46beefd2318d711b790f9a6cc9f9e832b2b1, concerning change to beta-tester groups
Add failing test for [LMS-1528]

Also cleans up test_view_authentication to use user factories for
various user classes
Fix [LMS-1528] (500 error when checking for beta access)