code: function resolveToSource(callback) {
            return async.series([
              _.partial(self.resolveRelationships, req, draft, to.workflowLocale),
              _.partial(self.resolveRelationships, req, from, to.workflowLocale)
            ], callback);
          }
docs: Resolve relationship ids in the "from" document (which will have been in a draft locale) and in the "draft" document (where we are exporting to) to point to a consistent locale, so that the diff applies properly