public ActionResult Create(UserAdd model)
 {
     if (ModelState.IsValid)
     {
         superUserRepo = new SuperuserRepo(context, HttpContext.GetOwinContext().GetUserManager<ApplicationUserManager>());
         superUserRepo.Create(model);
         return RedirectToAction("Index");
     }
     return View(model);
 }
 // Danh sach Superuser
 public ActionResult Index()
 {
     superUserRepo = new SuperuserRepo();
     return View();
 }