debugging unique user
Adding 123done happy path testing.
Make this an env variable, per Edwin's suggestion.
Added link-from-link-from email and logout clicks.

The link in the email only brings you halfway here; the link on the
landing page also needs to be verified.  But then we should make sure
that the logout link works, too, to get us back in our original state.
Minimum number of sleeps.  Ugh.
Conflicts.  Urgh.