Added logon() method to casAuthenticator class (refs #4052)
Removed param 'cookie' on casAuthenticator (refs #4064)

Use Session::PARAMNAME if it exists, or fallback to 'freedom_auth'.
Corrected PHP notices (refs #4062)
Merge pull request #6 from eguaj/0.2-integration

(closes #4052)(closes #4064)(closes #4062)