public function index()
    {
        $this->defaultData();
        $rolesc = new \core_kernel_classes_Class(GenerisRdf::CLASS_ROLE);
        $roles = array();
        foreach ($rolesc->getInstances(true) as $id => $r) {
            $roles[] = array('id' => $id, 'label' => $r->getLabel());
        }
        usort($roles, function($a, $b) {
        	return strcmp($a['label'],$b['label']);
        });

        $this->setData('roles', $roles);
        $this->setView('list.tpl');
    }