Bug 130492 Provide a method to serialize the report with library information.
Currently, when engine generate the report document file, the document does not contain any library information. That will cause many propblem on server side. Model should provide a method to serialize the report with library information to a stream so that the generated report document can contain all information that the report need.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
/**
	 * Sends an event called by the notification framework. The default
	 * implementation sends the event to listeners of this one object. Derived
	 * classes override this to send it to additional associated objects
	 * depending on context. The subclass should set the event's delivery path
	 * to indicate these additional delivery routes.
	 * <p>
	 * Part of: Notification system.
	 * 
	 * @param ev
	 *            the event to send
	 */
	public void sendEvent( NotificationEvent ev )
	{
		ev.setDeliveryPath( NotificationEvent.DIRECT );
		broadcast( ev );
	}
	/**
	 * Gets the root node of the design tree. This node must be a instance of
	 * <code>ReportDesign</code> or <code>Library</code>.
	 * 
	 * @return the root node of the design tree
	 */
	public Module getRoot( )
	{
		DesignElement element = this;
		while ( element.getContainer( ) != null )
			element = element.getContainer( );
		if ( element instanceof Module == false )
			return null;