Allow operator shelves to contain grouped apps.

r? @diox @ngokevin 

I have a few tests failing locally, but I'm pretty sure it's an ES misconfiguration and not an actual problem. I'll see what CI thinks.
I'm going to commit like this, as QA is starting soon, and will file a bug blocking this project to improve the structure of our index here. I'll work on it while @krupa is doing her thing. That sound alright to you, @robhudson?