Allow modules to query the MPM about it's execution profile. This

query API can and should be extended in the future, but for now,
max_daemons, and threading or forking is a very good start.

Non-Unix MPM's do have the MPM query function, although there is no
garauntee that the information is perfect, please check.

Submitted by:	Jon Travis <jtravis@covalent.net>


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@88437 13f79535-47bb-0310-9956-ffa450edef68