Menu:ItemEntry(MD,CurSize,aAccelerators):  private: return true
  Internal method by which is the submenu processed when the user selects
  the item. This method is often processed recursive (by submenus).

  Parameter description:
  ~~~~~~~~~~~~~~~~~~~~~~
  MD: object_of_MD: no default
   Submenu for this method (to be processed), its data structure is MD.
   The processing is to display the submenu and to select the item by
   the user.

  CurSize:
   The item width of current submenu.

  aAccelerators: array: default is {}
   The same as in BarEntry() method.