AMQP-306 Dynamic Consumers

JIRA: https://jira.springsource.org/browse/AMQP-306

- Allow the concurrentConsumers to be modified on a running container
-- add or remove consumers as necessary
- Add maxConcurrentConsumers
-- New consumer started at the max rate of 1 every 10 seconds and only if another consumer processes 10 consecutive messages
-- Idle consumer stopped if 60 consecutive timeouts (default 1 second each) no more than one consumer stopped per minute
INT-306 Polishing; Namespace; Docs

- PR comments
- Add Configurable Start/Stop Algorithm Properties
- Namespace Support
- Docs

Also:

Add `receive-timeout` to namespace.

JIRA: https://jira.springsource.org/browse/AMQP-264