This is a huge change to the configure system. Basically, this name space

protects most, if not all, of the Apache macros.   This has been tested on
Linux using all of the Unix MPM's.  The biggest push was that Apache's
httpd.h header file can no longer include the ap_config.h file.  Most of the
other files include this themselves now.
Submitted by:	Ryan Bloom and Manoj Kasichainula


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@84492 13f79535-47bb-0310-9956-ffa450edef68