private void GMBManageLibraryMenuItemClicked(object sender, RoutedEventArgs e)
        {
            ManageLibrary libWindow = new ManageLibrary();

            libWindow.Show();
        }
 private void GMBManageLibraryMenuItemClicked(object sender, RoutedEventArgs e)
 {
     ManageLibrary libWindow = new ManageLibrary();
     libWindow.Show();
 }