Allow InterceptHandler to specify the messages they can intercept. This allows us to improve the performance of the broker interceptor, and will make log traces more clear.

- Add methods to return an unique identifier and the supported message types at the InterceptHandler interface.
- Include a default implementation of the new methods in the AbstractInterceptHandler. By default, all the interceptors will be able to handle any message (same as before).
- Comment verifyNoMoreInteractions() call from the BrokerInterceptorTest.testAddAndRemoveInterceptHandler(). The removeInterceptHandler() method of the broker interceptor
  polls the InterceptHandler, so an interaction will always exist after the call to onSubscribe().

broker/src/main/java/io/moquette/interception/HazelcastInterceptHandler.java

@@ -18,6 +18,11 @@ public class HazelcastInterceptHandler extends AbstractInterceptHandler {
     public HazelcastInterceptHandler(Server server){
         this.hz = server.getHazelcastInstance();
     }
+    
+    @Override
+    public String getID() {
+    	return HazelcastInterceptHandler.class.getName() + "@" + hz.getName();
+    }
 
     @Override
     public void onPublish(InterceptPublishMessage msg) {