/**
  * Método para cargar usuarios de prueba
  */
 private function loadUsers(ObjectManager $manager, $username, $email, $password, $roles)
 {
     $date = new \DateTime(date('Y-m-d H:i:s'));
     $user = new Users();
     $user->setSalt(md5(uniqid(null, true)));
     $encoder = $this->container->get('security.password_encoder');
     $pass = $encoder->encodePassword($password, $user->getSalt());
     $user->setUsername($username);
     $user->setEmail($email);
     $user->setPassword($pass);
     $user->setActive(1);
     $user->setRoles($roles);
     $user->setCreatedAt($date);
     $user->setModifiedAt($date);
     $user->setCreatedBy(1);
     $manager->persist($user);
     unset($user);
     $manager->flush();
 }