message: Add a missing link target, and add a missing space.
diff: When over 50% of http fetch attempts inside a 30-minute period fail, pagespeed will now emit
  an error entry to the logs.
  </dd>
  - <dt><a href="">Off</a> has been replaced by<a href="configuration#standby">Standby</a></dt>
  + <dt><a href="configuration#on_off">Off</a> has been replaced by <a href="configuration#standby">Standby</a></dt>
  <dd>
  In standby mode PageSpeed is off, except it serves .pagespeed. resources and
  PageSpeed query parameters are interpreted. This is equivalent to "off" in
  