People lookup: display names

[adehnert]

For MIT users, it would be nice to display people's actual name as well as the username that got entered. We're already finding them in LDAP, so this shouldn't be hard. This is useful for people with a big list of all members' email addresses and another list of actual names (not usernames) of people who are active -- they can look up their whole membership list and cross-reference it with their active names and count up by category, without (say) doing the LDAP lookups themselves.