/** * add a sublist (nlobjSubList) to this form and return it. * * @param {string} name sublist name * @param {string} type sublist type: inlineeditor|editor|list|staticlist * @param {string} label sublist label * @param {string} [tab] parent tab that this sublist lives on. If empty, it is added to the main tab * @return {nlobjSubList} * * @since 2008.2 */