Fixes bug in TaskProducer (deprecated class)
Adds setting to modify the heartbeat monitor rate: BROKER_HEARTBEAT_CHECKRATE
Changes "command-line" -> "command line"
amqp backend: polling now uses message.requeue instead of republishing
contextmanagers that needs finally
Fixes deprecation message
Merge branch '3.0' of github.com:celery/celery into 3.0