private async void btnCloseCard_Clicked(object sender, EventArgs e)
        {
            TrelloCard card = (sender as Button).BindingContext as TrelloCard;

            card.IsClosed = true;
            await TrelloRepository.UpdateCardAsync(card);

            loadListAsync();
        }
        private async void btnSave_Clicked(object sender, EventArgs e)
        {
            TrelloCard card = new TrelloCard()
            {
                Name = editName.Text
            };

            if (IsNewCard)
            {
                await TrelloRepository.AddCardAsync(this.Card.List.ListId, card);
            }
            else
            {
                Card.Name = card.Name;
                await TrelloRepository.UpdateCardAsync(Card);
            }
            Navigation.PopAsync();
        }