better UI for update interface

[geofft]

Currently when you update anything in the DB, you get a confirmation page showing _everything_, not just your change, and you also get thrown back to the main page once you confirm.

Better yet would be a confirmation of just your change, and to be sent back to the group's page. Alternatively, there's a fairly common web UI design pattern these days of sending you back to the page with each change listed in a highlighted bar at the top, possibly with an undo button.

Also, updating signatories should happen on the same page instead of o a separate one.

[adehnert]

Do I need to care about this?