Record and show relationship of objects

[SilverRainZ]

Cross references

• Add an .. any:obj.xref:: {{ unique }} directive for listing cross references of object?
• Record the references relationshipAnyDomain.process_xref
  • document -> object
  • object -> object (and the revverse reference)

Parent

• Add a {{ parent }} template variable for object
• Maintain an object stack when calling a directive's run method, so we can know the parent of objects.