* check_session.c: added more CANCEL cases
2.2.5 - CANCEL glare test case (failing)
2.2.6 - Simple nua UAS CANCEL case
2.2.7 - RFC 2543 client CANCELing, nua as UAS
git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@9511 d0543943-73ff-0310-b7d9-9358b9ac24b2