I know this one can be done. I've been digging, but can't seem to figure it out.

I'm using the bundle editor to create a bunch of snippets.  Because I have to create so many of them, I like them categorized.

I'm looking to do something similar to what I see in the CSS > Background bundle.  That is, a top-level category of snippets, plus sub-menus that contain other snippets.

How does one go about setting this up?

Thanks.

- Scott