Includes a reload and update command.
Reload sends a SIGHUP to the gunicorn process. This does a graceful reload if the preload
option isn't set.
Update sends a SIGUSR2 which starts a new master process. It then sends a QUIT to the old process, which gracefully shuts it down after all connections are closed. This works with the preload
option.
I got the idea from Benoit's comment, here: