Committing fix for MH-6244 into trunk.

git-svn-id: https://opencast.jira.com/svn/MH/trunk@13788 e6edf6fb-f266-4316-afb4-e53d95876a76
MH-9399 -- cache organizations to reduce DB access

git-svn-id: https://opencast.jira.com/svn/MH/trunk@13791 e6edf6fb-f266-4316-afb4-e53d95876a76