Update the Jetty WebSocket adapter

This changes switches from using Jetty's WebSocketListener interface
to use Jetty's @WebSocket annotations instead. The change should be
transparent but the annnotations provide a little more controler
including handling pong frames.

This change also introduces a WebSocketMessage interface.

Issue: SPR-10877

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/support/MessageHandlingException.java

@@ -28,6 +28,8 @@ import org.springframework.messaging.MessagingException;
  */
 public class MessageHandlingException extends MessagingException {
 
+	private static final long serialVersionUID = 690969923668400297L;
+
 
 	public MessageHandlingException(Message<?> message, String description, Throwable cause) {
 		super(message, description, cause);

spring-messaging/src/main/java/org/springframework/messaging/simp/BrokerAvailabilityEvent.java

@@ -26,8 +26,11 @@ import org.springframework.context.ApplicationEvent;
  */
 public class BrokerAvailabilityEvent extends ApplicationEvent {
 
+	private static final long serialVersionUID = -8156742505179181002L;
+
 	private final boolean brokerAvailable;
 
+
 	/**
 	 * Creates a new {@code BrokerAvailabilityEvent}.
 	 *