code cleanup, saving some apr_time_now() calls on scheduling, worker now only...

code cleanup, saving some apr_time_now() calls on scheduling, worker now only sticky to a connection when idle workers are present

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1731963 13f79535-47bb-0310-9956-ffa450edef68