SAK-27931 - Add descriptive note for course points feature.


git-svn-id: https://source.sakaiproject.org/svn/gradebook/trunk@313914 66ffb92e-73f9-0310-93c1-f5514f145a0a
SAK-27936 - If student has no assignments graded course points shows 0/-1


git-svn-id: https://source.sakaiproject.org/svn/gradebook/trunk@313915 66ffb92e-73f9-0310-93c1-f5514f145a0a