Compares this instance with the specified
MonoTouch.AddressBook.ABPerson and returns an
integer that indicates whether this instance precedes, follows,
or appears in the same position in the sort order as
other.
Compares this instance with the specified
MonoTouch.AddressBook.ABPerson and returns an
integer that indicates whether this instance precedes, follows,
or appears in the same position in the sort order as
other (as controlled by ordering).