Close popovers with Escape and clicking outside them

Unless the popover requires action (as when uploading a PGP key or adding a proof) they should close when I click outside them or press `Escape`. Much more convenient than using the `x`.

When inspecting someone's PGP key is one example.

No files or tests are named. Start by locating the popover implementation and the flow for inspecting someone's PGP key; check which popovers require an action before dismissal. Done means non-action popovers close on Escape or an outside click while action-required popovers remain open.

Written by the indexing model from the issue text.