Performance: Add quick_handler hook. This hook is called at the

very beginning of the request processing before location_walk,
translate_name, etc.  This hook is useful for URI keyed content
caches like Mike Abbott's Quick Shortcut Cache.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@88596 13f79535-47bb-0310-9956-ffa450edef68