Add a new MPM. Currently this is almost an exact copy of the dexter MPM.

In time, this will be the MPM that allows each child process to have a
unique user id.  I need a place to work and keep track of my changes.
Don't expect this to work until next week sometime.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@85902 13f79535-47bb-0310-9956-ffa450edef68