protected function addOrchestraHierarchy(ContainerBuilder $container, LoaderInterface $loader)
    {
        $loader->load('security.yml');

        $orchestraHierarchy = $container->getParameter('open_orchestra_user_admin.role_hierarchy');
        $roleHierarchy = array();
        if ($container->hasParameter('security.role_hierarchy.roles')) {
            $roleHierarchy = $container->getParameter('security.role_hierarchy.roles');
        }

        $container->setParameter('security.role_hierarchy.roles', array_merge($orchestraHierarchy, $roleHierarchy));
    }