Log out button should have a confirmation dialogue box

More than once I've accidentally logged out of Keybase by accident and I (and probably many others used to having one) would like it if there were a confirmation dialogue box when trying to do such rather critical modifications to the behaviour of the client.

No file, test, or entry point is identified in the issue; start by locating the client's log-out button and its current action. Done means attempting to log out presents a confirmation dialogue and cancellation leaves the client logged in.

Written by the indexing model from the issue text.