docs: function _processHeaders(siteDesc, prefix) {
  
      if (!siteDesc.headers) {
          return;
      }
      //console.log('headers', siteDesc.headers, 'prefix', prefix);
      let headers = siteDesc.headers;
      let isInSiteStructure = false;
      if (siteDescriptionReader.checkParams(siteDesc.requiredParams)) {
          isInSiteStructure = true;
      }
      for (let i in headers) {
          _processElement(headers[i], prefix, { isInSiteStructure: isInSiteStructure });
      }
  }