Completes the rewrite of the RewriteMap documentation. Examples for all

the various map types, and an overhaul from a grammar perspective. Still
want to do some tweaks on the ref doc side.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@946438 13f79535-47bb-0310-9956-ffa450edef68