This patch reduces the number of time()/gettimeofday() system calls when

This patch reduces the number of time()/gettimeofday() system calls when
doing high volume processing.  This enables about 25% speed increase
during journal replay and "BATCH" processing.  (this is a function of
syscall overhead).

 * note when "BATCH" processing or journal replay starts, use that
   timestamp for all commands

 * use the batch start time to detect when we're in batch mode.  no longer
   need a separate boolean.

 * pass the time_t into handle_request

 * pass the time_t through to the commands that need it

-- kevin brintnall

git-svn-id: svn://svn.oetiker.ch/rrdtool/trunk@1599 a5681a0c-68f1-0310-ab6d-d61299d08faa