private void AddedCluesList_KeyDown(object sender, KeyEventArgs e)
        {
            ListBox box = sender as ListBox;

            if (box.SelectedItem != null && e.Key == Key.Delete)
            {
                AddedClues.Remove(box.SelectedItem as string);
            }
        }
        private void CluesList_Drop(object sender, DragEventArgs e)
        {
            if (e.Data.GetDataPresent(DataFormats.Text))
            {
                string clueString = (string)e.Data.GetData(DataFormats.Text);
                if (Clue.ValidateString(clueString) == true && ClueManager.Manager.GetTreeNode(new Clue(clueString)) != null)
                {
                    // Add text to panel display
                    AddedClues.Add(clueString);
                }
            }

            // Hide additional feedback
            DocumentDropCursorText.Visibility = Visibility.Collapsed;
        }