SAK-24180

More rawness in the oauth body hashing.



git-svn-id: https://source.sakaiproject.org/svn/basiclti/branches/BLTI-230@131219 66ffb92e-73f9-0310-93c1-f5514f145a0a
SAK-24180

Tweaks identified by the certification test.



git-svn-id: https://source.sakaiproject.org/svn/basiclti/branches/BLTI-230@131231 66ffb92e-73f9-0310-93c1-f5514f145a0a