code: public URLNormalizer removeTrailingQuestionMark() {
          if (url.endsWith("?") && StringUtils.countMatches(url, "?") == 1) {
              url = StringUtils.removeEnd(url, "?");
          }
          return this;
      }
docs: <p>Removes trailing question mark ("?").</p>
  <code>http://www.example.com/display? &rarr;
  http://www.example.com/display </code>
  @return this instance