Merge branch 'upstream/master'
CAS-1284: Validate and adopt CAS3 protocol rev
 - removed "url" parameter from /logout as discussed in dev-ml.
 - rev. 3.0 RC2
 - minor fixes, state CAS 4.0 as protocol 3.0 compliant.
Merge pull request #413 from robertoschwald/master

CAS-1284: Validate and adopt CAS3 protocol rev