[PLG_COURSES_DISCUSSIONS] Fixing incorrect language key names
[PLG_COURSES_DISCUSSIONS] Fixing incorrect language key names

anthonyfuentes/hubzero-cms,anthonyfuentes/hubzero-cms,zooley/hubzero-cms,zooley/hubzero-cms,zooley/hubzero-cms,zooley/hubzero-cms,zweidner/hubzero-cms,zweidner/hubzero-cms,zweidner/hubzero-cms,anthonyfuentes/hubzero-cms,zweidner/hubzero-cms,anthonyfuentes/hubzero-cms