public function load(DocumentManager $manager)
 {
     $userAdmin = new User();
     $userAdmin->setUsername('admin');
     $userAdmin->setSalt(md5(uniqid()));
     $plainPassword = '******';
     $encoder = $this->container->get('security.password_encoder');
     $password = $encoder->encodePassword($userAdmin, $plainPassword);
     $userAdmin->setPassword($password);
     $userAdmin->setRoles(array("ROLE_ADMIN"));
     $manager->persist($userAdmin);
     $manager->flush();
 }