1.2.1

The channels opened by this library are now QoS'd. This changes the default RabbitMQ behavior from blindly round robining messages to workers to instead deliver to workers that are idle. In most circumstances this change is uneventful, but it helps to avoid 1 in N pileup when say one particularly heavy piece of work comes through and blocks one worker for a period of time. Now other workers will continue to perform the other work instead of that one worker's queue starting to back up.

This setting is configurable in the constructors for Client and Dispatcher via the prefetch_count argument.