Gets all split entities, per target. A split entity is really a group of entities which are mapped onto the same target and which all have 1:1 pk-pk relationships with one entity in their group. If A, B, C and D are mapped onto the same target T and B and D have a 1:1 pk-pk relationship towards A (pkside), and C does not, it means that B and D are 'split off' of A. C is not part of the split and is ignored. Returned is then A with its split off companions B and D. A is then returned as key with values B and D.

public MultiValueDictionary<EntityDefinition, EntityDefinition> GetAllSplitOffEntities(
	string driverID
)

Public Function GetAllSplitOffEntities ( 
	driverID As String
) As MultiValueDictionary(Of EntityDefinition, EntityDefinition)