I'm writing a bundle and I would like to add create some submenus.

I understand that the association, and ordering, of commands in bundle menus is achieved via the `info.plist` property list for the bundle. New commands are generated with an ID number that can be referenced in the `info.plist`.

Submenus also have ID numbers that appear in the bundle's `info.plist`. However, these submenu ID numbers don't appear to be generated, or to feature, elsewhere in the bundle.

My question is: how does one create the ID numbers for submenus in `info.plist`? Would any random ID that is distinct from the others in the `info.plist` do? What about collisions with numbers in other bundles? How do folks usually generate these submenu ID numbers?

Final question: is there any faster way to manage menu structure of a bundle other than fiddling by hand with `info.plist`?