Merge r1636195 from trunk:

namded captures show up in the env with a MATCH_ prefix.
   http://httpd.apache.org/docs/2.4/sections.html#comment_3193



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1636196 13f79535-47bb-0310-9956-ffa450edef68