pub fn mail_address(person: &RosterPerson) -> Option<DbSecret>Expand description
The address a linking mail to person goes to, if Sisu holds one: the primary, else the
secondary.
Sisu verifies neither, so the confirmation page shows the Sisu name to make a planted address harder to exploit. Open University students without a University account often have only a secondary address, and Sisu clears old primaries.