public async Task Delete(string id)
        {
            HttpClient cliente = await Detalle.getConection();

            await cliente.DeleteAsync(Detalle.url + "/" + id);

            var servicioM = DependencyService.Get <InterfazMensaje>().GetMensaje("Contacto eliminado");

            Detalle.ConvertirTextoAVoz(servicioM);
            await DisplayAlert("Mensaje Dependency", servicioM, "Ok");
        }
        public async Task Update(string id, string firstname, string lastname, string phoneNumber, string email)
        {
            ContactoAPI contact = new ContactoAPI()
            {
                Id          = id,
                firstname   = firstname,
                lastname    = lastname,
                phoneNumber = phoneNumber,
                email       = email
            };

            System.Diagnostics.Debug.Write(id + " HOLA MUNDO");
            HttpClient cliente = await Detalle.getConection();

            await cliente.PutAsync(Detalle.url + "/" + id, new StringContent(JsonConvert.SerializeObject(contact), Encoding.UTF8, "application/json"));
        }
        public async Task <ContactoAPI> Post(string id, string firstname, string lastname, string phoneNumber, string email)
        {
            ContactoAPI contact = new ContactoAPI()
            {
                Id          = "",
                firstname   = firstname,
                lastname    = lastname,
                phoneNumber = phoneNumber,
                email       = email
            };
            HttpClient cliente = await Detalle.getConection();

            var response = await cliente.PostAsync(Detalle.url,
                                                   new StringContent(JsonConvert.SerializeObject(contact), Encoding.UTF8, "application/json"));

            return(JsonConvert.DeserializeObject <ContactoAPI>(await response.Content.ReadAsStringAsync()));
        }