Aoache -> Apache typo.

      <p>When content expires from the cache and is re-requested from the 

      backend or content provider, rather than pass on the original request,

      Aoache will use a conditional request instead.</p>

      Apache will use a conditional request instead.</p>

      <p>HTTP offers a number of headers which allow a client, or cache

      to discern between different versions of the same content. For