The following steps describe how a third party application can add menu items to the menu system:
              Install desktop entries to
              datadir/applications/ for each menu
              item. Please namespace the filename, as in "vendor-foo.desktop", or
              use a subdirectory of
              datadir/applications/ so you have
              "vendor/foo.desktop." Please be sure all desktop entries are valid
              (see the 
              desktop-file-utils package for a validation utility).
            
              Install an XML menu file to sysconfdir/menus/applications-merged/ to add any submenus, if your desktop entries aren't already 
              included in some common categories.
            
              Install any directory entries needed for your submenus to datadir/desktop-directories/, taking care to namespace and validate
              the directory entries.