Helper to perform Assignment using Diffo.Provider.AssignedToRelationship.
Assignment state is stored on AssignedToRelationship nodes (pool, thing, assigned),
distinct from regular TMF Diffo.Provider.Relationship nodes.
Summary
Functions
Assign a thing using the pool declared via pools do on the instance module.
The thing name is looked up from the pool declaration.
Assign a thing using the instance changeset assignment.