def drop_contact person
    aalias = @p2a[person]
    @p2a.delete person
    @e2p.delete person.email
    @a2p.delete aalias if aalias
  end
def drop_contact person
    aalias = @p2a[person]
    @p2a.delete person
    @e2p.delete person.email
    @a2p.delete aalias if aalias
  end
this may not actually be called anywhere, since we still keep contacts
 around without aliases to override any fullname changes.