Required library edition:
Required library file: dhtmlxmenu.js

adds a new child item

• parentId - the item which will contain a new item in the sublevel
• position - the position of a new item
• itemId - id of a new item
• itemText - text of a new item
• disabled - true|false, whether the item is disabled or not
• img - image for the enabled item
• imgDis - image for the disabled item

    menu.addNewChild(parentId, pos, itemId, itemText, disabled, imgEnabled, imgDisabled);