Added a feature that allows you to run group commands synchronously instead of in parallel

- New config variables for process:
  process.group_start_noblock
  process.group_stop_noblock
  process.group_restart_noblock
  process.group_unmonitor_noblock

- group_*_noblock option defaults to true.
Changed blocking mode log message to debug.
Merge with - Allow group commands to be run synchronously