public ActionResult Edit(Contact contact)
        {
            try
            {
                using (var tx = _session.BeginTransaction())
                {
                    _session.SaveOrUpdate(contact);
                    tx.Commit();
                }
 
                return RedirectToAction("Index");
            }
            catch
            {
                return View();
            }
        }
        public ActionResult Create(Contact contact)
        {
            try
            {
                using (var tx = _session.BeginTransaction())
                {
                    _session.SaveOrUpdate(contact);
                    tx.Commit();
                }

                return RedirectToAction("Index");
            }
            catch(Exception ex)
            {
                ModelState.AddModelError("contact", ex.ToString());
                return View();
            }
        }