Add validations to groups form

[thestrabusiness]

Address #32

[simonkernel]

Hi @thestrabusiness,

Thanks for working on this and apologizes for just getting to this now!

We have @mgorkove with PR #40 in flight right now as well which will impact the Form component and validation.

I like the general approach and we're sort of re-implementing validation and alerts in each app. It would be great to keep things generic where possible.

Not saying we have to be able to use right away, just if there's a path to eventually extract it so to just keep it in mind.

I'd say let's hold off until the autocomplete PR lands and apologies for the cross-over.