public JsonResult Edit(ChamadaModel chamadaModel)
 {
     try
     {
         var chamada = _servicoDeChamada.GetById(chamadaModel.Id);
         chamada.Presenca = chamadaModel.Presenca;
         return Json(_servicoDeChamada.Alterar(chamada));
     }
     catch
     {
         return Json(false);
     }
 }
 public JsonResult Create(ChamadaModel chamadaModel)
 {
     try
     {
         var chamada = Mapper.Map<Chamada>(chamadaModel);
         return Json(_servicoDeChamada.Adicionar(chamada));
     }
     catch
     {
         return Json(false);
     }
 }