fixed nextCatalog started adding a small regression test Daniel

* catalog.c: fixed nextCatalog
* result/catalogs/docbook test/catalogs/*: started adding
  a small regression test
Daniel
diff --git a/catalog.c b/catalog.c
index d645d88..21270d4 100644
--- a/catalog.c
+++ b/catalog.c
@@ -1018,7 +1018,9 @@
 		    xmlFetchXMLCatalogFile(cur);
 		}
 		if (cur->children != NULL) {
-		    xmlCatalogListXMLResolve(cur->children, pubID, sysID);
+		    ret = xmlCatalogListXMLResolve(cur->children, pubID, sysID);
+		    if (ret != NULL)
+			return(ret);
 		}
 	    }
 	    cur = cur->next;