Upgrade protocol version to 1.1. Clean up persistent connection support

a bit.

Reviewed by: Rob Hartill, Jim Jagielski, Chuck Murcko, Roy T. Fielding


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@76779 13f79535-47bb-0310-9956-ffa450edef68