Fix issue #1295: Added a check to see if every group being collected had only one TA assigned to them.
Fix for issue 1295: DIsabled button if more than one TA is marking the same set of submissions.
Added check to second branch to make sure it fails for any user except for a TA.
Merged Master fixed conflict.
Added translations for French and Portuguese, also did some formatting.
Merge pull request #1428 from ealonas/issue-1295

Fix issue #1295: Check to see if every group being collected had only one TA assigned to them.