Make sure custom field labels are shown for batch execution dialog

tailbone/views/batch/core.py

@@ -747,6 +747,11 @@ class BatchMasterView(MasterView):
                     if key in self.request.session:
                         defaults[field.name] = self.request.session[key]
 
+                # make sure field label is preserved
+                if field.title:
+                    labels = kwargs.setdefault('labels', {})
+                    labels[field.name] = field.title
+
         else:
             schema = colander.Schema()