Improve the cache hit/miss ratio by canonicalising the url key. hostname's
are matched case-insensitively, port-based vhosts are catered for and the
scheme included for future multi-scheme caching compatibility.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@239407 13f79535-47bb-0310-9956-ffa450edef68