Add Übernahme Button to MainWindow

Elwig/Windows/MainWindow.xaml.cs

@@ -25,6 +25,11 @@ namespace Elwig.Windows {
             w.Show();
         }
 
+        private void ReceiptButton_Click(object sender, RoutedEventArgs evt) {
+            var w = new DeliveryAdminWindow(true);
+            w.Show();
+        }
+
         private void DeliveryAdminButton_Click(object sender, RoutedEventArgs evt) {
             var w = new DeliveryAdminWindow();
             w.Show();