Draft reform of the caching for party descendant types (persons, users, groups)
- new proc party::get to centralize caching of the various information for a party descendant scattered through tables
- allow to retrieve only a single value from the dict in new and existing api
- rename of user_info_cache with party_info_cache
- replacement into previously existing api
Behavior for the new proc now will be to not fail, just return an empty dict or an empty value when no party is found
TODO: after review of the change, replacement of all now deprecated calls in code around
