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
* @param propName
	 *            The internal name of the user-defined property.
	 * @return The user-defined property definition, if any.
	 */
	public UserPropertyDefn getLocalUserPropertyDefn( String propName )
	{
		if ( userProperties == null )
			return null;
		return (UserPropertyDefn) userProperties.get( propName );
	}
	/**
	 * Gets the definition of a user-defined property defined in this element or
	 * somewhere up the inheritance chain.
	 * <p>
	 * Part of: User-defined property system.
	 * 
	 * @param propName
	 *            The internal name of the user-defined property.
	 * @return The property definition, if found, null otherwise.
	 */
	public UserPropertyDefn getUserPropertyDefn( String propName )
	{
		DesignElement e = this;
		while ( e != null )
		{
			UserPropertyDefn p = e.getLocalUserPropertyDefn( propName );
			if ( p != null )
				return p;
			e = e.getExtendsElement( );
		}