Add sorting of student projects on organization home page. List of student projects on organization home page is now sorted in alphabetical order by student name. Fixes issue 613.

Now clicking cancel button returns user to previous page. Fixes issue 569. If you don't want that behaviour you can define cancel_redirect and user will be redirected to given url on "Cancel" button click instead of redirecting to previous page. Patch by: Daniel Hans & Pawel Solyga