Menu:AddMenu(cName,nHotKey,bPreBlock,bPostBlock): public: return true
  The current menu is appended with the next submenu item.

  Parameter description:
  ~~~~~~~~~~~~~~~~~~~~~~
  cName: character: no default
   Menu item name.

  nHotKey: numeric: no default
   It is InKey() key code, representing the "hot key" for this menu item.
   If not set the hot key is not created.

  bPreBlock: code_block: default is {||true}
   The code block, processed before entering this item.

  bPostBlock: code_block: default is {||true}
   The code block processed imediately after leaving the item.