Add process_rec to the top of {server,connection,request}_rec

hierarchy of structs that abstract server activities.  Store some
stuff in process_rec (finally a place to have nearly guiltless
globals) for example the global and configuration pools.  Put some
operations on process_rec in http_main, in particular the
destroy_and_exit operation, and the use it to do all the exit calls.
Change ap_read_config to operation on this "object" rather than on the
configuration pool.  Modify server_rec to point to the process, so you
can get at it most all the time which should finally allow most of the
server's malloc calls to be eliminated.

There are no locks in the process struct as yet, put them in as needed.
Some of the hooks should take this rather than conf. pool.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@83942 13f79535-47bb-0310-9956-ffa450edef68