Description:
+Call the append method to add a child menu item
+to the parent menu item in the options menu list. This results in the creation
+of a submenu list in the menu tree. Use this method to create a cascading
+submenu when needed.
Menu items are shown on the options menu list in the order in which +they are appended.
+Syntax:
+[void] MenuItem.append(MenuItem childMenuItem)+
Arguments:
+childMenuItem:
This is an instance of the MenuItem object
+which is being added to the parent menu item. See also the menu.append method description for instructions on how to append a menu item
+to the top level of the options menu list.
Return value:
+This method does not return a value.
+Remarks:
+For devices with a small screen, it is not practical to create multi-level +cascading submenus. Thus, a maximum of two-levels is recommended for submenus.
+Appending a new menu item fails if it tries to create a duplicate menu
+item (it either has the same id or the same label as
+an existing menu item).
For more general information on constructing an options menu, see Using softkeys.
+Example code:
+See the example code in the description of the MenuItem.onSelect property.