release-3.0.0

• DaemonController#initialize now uses keyword arguments.
• Changes defaults:
  • start_timeout: 15 -> 30
  • stop_timeout: 15 -> 30
  • log_file_activity_timeout: 7 -> 10
• Improves aborting daemon upon start timeout.
  • Before: we aborted the daemon by sending SIGTERM but without checking whether it actually terminates.
  • Now: aborting two stages: first abort gracefully (SIGTERM); if that times out (customizable via stop_abort_timeout), then abort forcefully (SIGKILL).
• Allows customizing the stop signal sent by DaemonController#stop, via stop_graceful_signal.
• More robust general timeout handling. Instead of timing out at any point in the code (which could leave behind inconsistent state), only allow timing out in well-defined interruption points.