INT-3579: AMQP Stop the Template if a Lifecycle

JIRA: https://jira.spring.io/browse/INT-3579

Implement `Lifecycle` in the AMQP outbound adapter and propagate
a `stop()` to the `AmqpTemplate` if it implements `Lifecycle`.

Delegate `isRunning()` to the `AmqpTemplate` instead of permanent `true`.