API 2: Contact API enhancements

It seems API 2 for contacts does not support (getting, setting) all the contact properties that were supported in API 1. In particular, the following fields are not supported: 'custom_greeting', 'gender', 'greeting_type', 'preferred_communication_method', 'prefix', 'prefix_id', 'suffix', 'suffix_id', 'source'.

Please add as much of them to API 2 for contacts as possible for CiviCRM 2.0, so dedupe (which was ported from API 1 to API 2) has as few regressions (ideally, none) in 2.0 as possible.