public ActionResult SignIn(String email, String password)
        {
            int id = cs.CheckAuthenticity(email, password);

            if (id != 0)
            {
                FormsAuthentication.SetAuthCookie(email, false);
                return(RedirectToAction("CustomerIndex", "Index", new { CustomerId = id }));
            }
            else
            {
                TempData["check"] = "Failed";
                return(RedirectToAction("Index"));
            }
        }