rewrote http2 connection state handling, fixed keepalive timeout handling for...

rewrote http2 connection state handling, fixed keepalive timeout handling for async and sync MPMs, cleaned logging, improved scoreboard updates of http2 master connections

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1721417 13f79535-47bb-0310-9956-ffa450edef68