Suggestion: CardButton and AtomButton Components

[dbchristopher]

I think it could be helpful to have out-of-the-box support for card and atom integration in the toolbar. I have CardButton and AtomButton components set up in my own project. I'd be happy to open a PR to include them here if you think that could be helpful addition to this repo.

[joshfrench]

I've avoided doing this to date because given the open-ended nature of cards & atoms, I wasn't sure there was a solution that was generic and broadly useful. If you want, open a PR with your implementation for more discussion though.

[gpoitch]

Happy to discus in a PR