cleaned up method getCourseIdAndTitleForLearnerGroup(): rewrote query to use JOINs, added missing constraint for filtering out "deleted" offerings. added output sanitation to prevent SQL injections.
altered SQL query to include courses linked to groups via independent learning sessions. refs #3525
Merge pull request #128 from ucsflibtopfstedt/bug3525

altered SQL query to include courses linked to groups via independent…