code: function extractHeaderCookies(headerSet) {
      var cookie = headerSet.cookie;
      var cookies = cookie ? cookie.split(';') : [];
      delete headerSet.cookie;
      return cookies;
  }
docs: Pull out the cookie from a header set. It is assumed that there is a max of 1 cookie header per header set. The
  cookie is removed from the headerSet if found.
  
  @param {Object} headerSet the set of headers from which to extract the cookies