Merge r1554300, r1554301, r1554994, r1555266 from trunk:
core: Support named groups and backreferences within the LocationMatch,
DirectoryMatch, FilesMatch and ProxyMatch directives.
Documentation for the support of named groups and backreferences.
c89 fix
Add a "MATCH_" prefix to variables set within
LocationMatch/DirectoryMatch/FilesMatch.
Submitted by: minfrin, covener, minfrin
Reviewed/backported by: jim
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@
1555551 13f79535-47bb-0310-9956-
ffa450edef68