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 null;
		return theme.getName( );
	}
	/**
	 * Returns the resolved theme of the report design/library.
	 * 
	 * @param module
	 *            the module to resolve the theme
	 * @return the resolved theme of the report design/library
	 */
	public Theme getTheme( Module module )
	{
		if ( theme == null )
			return null;
		if ( theme.isResolved( ) )
			return (Theme) theme.getElement( );
		ElementRefValue refValue = nameHelper.resolve( ReferenceValueUtil
				.needTheNamespacePrefix( theme, this ), null,
				MetaDataDictionary.getInstance( ).getElement(
						ReportDesignConstants.THEME_ITEM ) );
		Theme target = null;
		if ( refValue.isResolved( ) )
		{
			target = (Theme) refValue.getElement( );
			theme.resolve( target );
			target.addClient( this, THEME_PROP );
		}
		return target;
	}
	/**