public ActionResult Edit(UserModel model)
        {
            if (ModelState.IsValid)
            {
                var user = _userService.UpdateUser(model.User);

                _roleService.UpdateUserRoles(user.Id, model.UserRoleIds);

                return RedirectToAction("Index");
            }
            return View(model);
        }
        public ActionResult Create(UserModel model)
        {
            if (ModelState.IsValid)
            {
                var user = _userService.CreateUser(model.User.Name, model.User.EmailAddress, model.User.Discount);

                _roleService.UpdateUserRoles(user.Id, model.UserRoleIds);

                return RedirectToAction("Index");
            }

            return View(model);
        }