fix render without option

jsonform.gadget.js

@@ -864,6 +864,9 @@
     })
 
     .declareMethod('render', function (options) {
+      if (!options) {
+        options = {};
+      }
       var z = {
         saveOrigValue: options.saveOrigValue,
         editable: options.editable === undefined ? true : options.editable