Callback into the aggregator to manipulate a link mapping.
This is a callback provided by the IndividualAggregator whenever a 
            Persona.linkable_property_to_links method is called, 
            which should be called by the linkable_property_to_links implementation for each linkable-property-to-individual mapping it 
            wants to add or remove in the aggregator.
| link | the mapping string to be added to the IndividualAggregator | 
0.1.13