SAK-28098

A combination of fixes identified with Canvas interop testing 
as well as re-activating Re-Registration.   Still to come - 
handling the commit message send-back.



git-svn-id: https://source.sakaiproject.org/svn/basiclti/trunk@315623 66ffb92e-73f9-0310-93c1-f5514f145a0a