Support for handling different catchment areas

Before this ticket implementation will start, we should define the scope of this issue. What exactly means catchment areas ? How should we handle this ?

Acceptance Criteria:

1. Gather requirements, define the scope of this issue and update ticket description
2. Support for handling different catchment areas should be added - allow to configure what is synced where through configuration

UPDATE 08.10.2018

What exactly means catchment areas?
Catchment area means some additional conditions which objects must fulfill to be pulled from parent server (for instance we want to pull only patients from the specific department).

How should we handle this?
I think the best solution is creating strategies for different catchment areas. The strategy will help us choose which objects are interesting for us.

Acceptance criteria:

1. Support for handling different catchment areas should be added - allow to configure what is synced where through configuration
2. Update documentation