KNL-1029 fixes to allow embeds from library and from youtube alternates

git-svn-id: https://source.sakaiproject.org/svn/kernel/trunk@122059 66ffb92e-73f9-0310-93c1-f5514f145a0a
KNL-1029 extra test to confirm /access/library will not work

git-svn-id: https://source.sakaiproject.org/svn/kernel/trunk@122064 66ffb92e-73f9-0310-93c1-f5514f145a0a