private bool CheckUsername(List<User> user, LoginModel model)
        {
            bool found = false;

            foreach (var u in user)
            {
                if ((u.Username == model.Username && u.Password == model.Password))
                {
                    found = true;
                }
            }

            return found;
        }
        // GET: Login
        public ActionResult Index()
        {
            LoginModel model = new LoginModel();

            return PartialView(model);
        }