Int 3460: Support output-channel when an AbstractCorrelatingMessageHandler is 'ref'd by a Service Activator	

INT-3460: Support output-channel when an AbstractCorrelatingMessageHandler is 'ref'd by a Service Activator	

* allow AbstractCorrelatingMessageHandler's output referenced by service-activator output-channel
* add test 
```
 if (true == this.requiresReply && logger.isDebugEnabled()) {
      logger.debug("requires-reply can only be set to AbstractReplyProducingMessageHandler or its subclass, "
                     + handler.getComponentName() + " doesn't support it.");
 }
```
should be here too