title: Periodically CachingConnectionFactory creates each time new connection to check if queue is available
body: <p>I have application which dynamically creates the new SMLC to listening to the given queues.<br>
  But when the given queue does not exist on the RabbitMQ I have observed strange behaviour, i.e CachingConnectionFactory periodically creates each time new connection to check if queue is avaliable. What cause that threads count increase periodically - in my application reached ~ 4k threads.<br>
  1) Is it expected behaviour?<br>
  2) Is it possible to change this behaviour?<br>
  <strong>spring-amqp version 1.7.4.RELEASE</strong> </p>