NethVoice phonebook source must consider all levels of sharing

[Amygos]

The NethVoice administrator wants to import contacts from external sources and share them with everyone, groups of users, or a single user.

Importing into the NethVoice address book from external sources must consider the 3 levels of sharing, personal, group and public.

This means the sharing logic must be brought into the NethVoice address book.