KNL-1045 updated the result to allow for string grades

git-svn-id: https://source.sakaiproject.org/svn/kernel/trunk@123485 66ffb92e-73f9-0310-93c1-f5514f145a0a
KNL-1045 added notes about the proper way to encode grades

git-svn-id: https://source.sakaiproject.org/svn/kernel/trunk@123490 66ffb92e-73f9-0310-93c1-f5514f145a0a