Fix address sharing - full functionality

[bjendres]

In the course of the recent refactoring (reference needed) the address sharing functionality broke - even though it wasn't working properly anyway in some scenarios.

To fix this once and for all, we suggest a new line "share with" in the address processing panel with the following options:

1. update: if the changes should be applied to the current address and the master address (only if the current address is connected to a master)
2. unshare and update: if the changes should be applied to the current address but not the master address. Consequently, the link to the master address is therefore severed (only if the current address is connected to a master)
3. create and share: if the changes should be applied to the current address, and to a newly created master address with the submitted master_contact_id (only if the current address is not connected to a master)
4. create: if the changes should be applied to the current address, but not linked to a master address (only if the current address is not connected to a master)

Remarks:

• these options will be shown per location type
• there could potentially be more than master_contact_ids involved: a submitted one, and the current one.