Added meta tests for IDS

Change-Id: Iec1ca1dace8ae137ef03cd4f4d8be291548a9b69
diff --git a/t/sgbr/meta_duden.t b/t/sgbr/meta_duden.t
index cd82130..7cae3c5 100644
--- a/t/sgbr/meta_duden.t
+++ b/t/sgbr/meta_duden.t
@@ -29,6 +29,7 @@
 
 is($doc->publisher, 'Dorfblatt GmbH', 'Publisher');
 is($doc->pub_date, '20130126');
+is($doc->store('sgbrDate'), '2013-01-26');
 is($doc->pub_place, 'Stadtingen');
 
 is($doc->doc_title, 'Korpus zur Beobachtung des Schreibgebrauchs im Deutschen', 'Doc title');