message: Update release notes for 1.13.35.2-beta
diff: <div id=content>
  <h1>PageSpeed Release Notes</h1>
  + <h2 id="release_1.13.35.2-beta">Release 1.13.35.2-beta</h2>
  + <p>This release was made January 10, 2018.</p>
  + <h3 class="hide-from-toc">Issues Resolved</h3>
  + <h4 class="hide-from-toc">Issues Affecting both Nginx and Apache</h4>
  + <ul>
  + <li><strong>
  + <a href="https://github.com/apache/incubator-pagespeed-ngx/issues/1514">
  + #1514</a></strong>
  + Reliability fix for handling srcset attributes.</li>
  + </ul>
  + <h4 class="hide-from-toc">Issues Affecting only Nginx</h4>
  + <ul>
  + <li><strong>
  + <a href="https://github.com/apache/incubator-pagespeed-ngx/issues/1503">
  + #1503</a></strong>
  + CentOS 6: error: 'F_SETPIPE_SZ' was not declared in this scope .</li>
  + </ul>
  <h2 id="release_1.13.35.1-beta">Release 1.13.35.1-beta</h2>
  <p>This release was made November 8, 2017.</p>
  