title: reliable way to deploy new code into a production celery cluster without pausing service
body: <p>I have a few celery nodes running in production with rabbitmq and I have been handling deploys with service interruption. I have to take down the whole site in order to deploy new code out to celery. I have max tasks per child set to 1, so in theory, if I make changes to an existing task, they should take effect when the next time they are run, but what about registering new tasks? I know that restarting the daemon won't kill running workers, but instead will let them die on their own, but it still seems dangerous. Is there an elegant solution to this problem? </p>