Remove cookie handling code from CAS auth since its being handled upstream now.

application/modules/auth/controllers/IndexController.php

@@ -45,7 +45,6 @@ class Auth_IndexController extends App_Controller_Action {
 	public function logoutAction()
 	{
 		Zend_Auth::getInstance()->clearIdentity();
-		$this->_getCasAdapter()->clearIdentity();
 		$this->_redirect($this->_getCasAdapter()->getLogoutUrl());
 	}