public ActionResult Historial()
        {
            if (Request.Cookies["Sesion"] == null)
            {

                return RedirectToAction("Index", "Home");
            }
            else
            {
                HttpCookie aCookie = Request.Cookies["Sesion"];
                if (!aCookie["Tipo"].Equals("Coor"))
                    return RedirectToAction("Index", "Home");
                else
                    ViewBag.Texto = Server.HtmlEncode(aCookie.Values["Usuario"]);
            }

            Asistentes_TutoresEntities Datos = new Asistentes_TutoresEntities();
            List<string> Carnes;
            var carne = Datos.SP_BuscarEnHistorialCarne().ToList();
            Carnes = carne;
            ViewBag.Carnes = Carnes;
            return View();
        }