Move VAT ID into the footer

Change-Id: I612d485c45889b7f44fa1c5465bf34ee9b2f6b49
diff --git a/invoice.php b/invoice.php
index 1aa6927..dde7e85 100644
--- a/invoice.php
+++ b/invoice.php
@@ -83,11 +83,9 @@
 Commerzbank Mannheim
 Reference: ICLC-10-" . $user->id . "
 
-VAT ID: DE 143 845 359
-
 If you have any questions about this invoice, please contact us via buchhaltung@ids-mannheim.de.
 ");
-    //$invoice->setFooterNote("xx");
+    $invoice->setFooterNote("Leibniz-Institute for the German Language, Civil Law Foundation, VAT ID: DE 143 845 359");
 
     /* Render */
     $ret = $invoice->render('example4.pdf', 'S'); /* I => Display on browser, D => Force Download, F => local path save, S => return document path */