start the process of changing HTTP request dispatching to do it based on *both* URI...

start the process of changing HTTP request dispatching to do it based on *both* URI and method, so that POST support can move into a module; move http.c's private function prototypes into _private.h

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@109762 65c4cc65-6c06-0410-ace0-fbb531ad65f3