Tweaked some labels on the Email and Scoring Tools page and added well formatting to form for Gateway sets on Student Progress.
- Tweaked some things on the Achievment Editor Page.  Some checkboxes didn't work and other minor things.
- Changed a few wordings in the defaults.config Course settings.
-  Fixed PGProblemEditor2 so that Append works with Gateway Sets
-  Restored append functionality to PGProblemEditor3