Bug 197228 Need updaet createdBy info when serialize the module
When open module, designer will pass the property map which contains the createdBy info. this info should be retained by moduleHandle and then be updated and written when doing serialization. Note if this info is null, model should not update it during serialization. This could happen for api users or third-party designer. For BIRT designer, it will guarantee this value always not null.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
return (DesignElement) idMap.get( new Long( id ) );
	}
	/**
	 * Returns the line number.
	 * 
	 * @param obj
	 *            the obj to query the line number, it can be
	 *            <code>DesignElement</code>, or <code>EmbeddedImage</code>,
	 *            or <code>IncludedLibrary</code>
	 * 
	 * @return the line number
	 */
	public int getLineNo( Object obj )
	{
		return lineNoInfo.get( obj );
	}
	/**
	 * Looks up line number of the element in xml source given an element ID.
	 * Returns 1 if no line number of the element exists with the given ID.
	 * 
	 * @param id
	 *            The id of the element to find.
	 * @return The line number of the element given the element id, or 1 if the
	 *         element can't be found or if IDs are not enabled.
	 * @deprecated {@link #getLineNo(Object)}
	 */
	final public int getLineNoByID( long id )
	{
		if ( lineNoInfo == null )
			return 1;