MH-9498 -- removed duplicate dot from "unknown" prefix

git-svn-id: http://opencast.jira.com/svn/MH/trunk@14001 e6edf6fb-f266-4316-afb4-e53d95876a76
MH-9504 -- added null check to duration property access

git-svn-id: http://opencast.jira.com/svn/MH/trunk@14002 e6edf6fb-f266-4316-afb4-e53d95876a76