anchor.diff:                  "referenceUrn" : "urn:uuid:12345",
                   "type" : "Owns",
                   "relatedEntityReferenceType": "Object",
  -                "relatedReferenceURN" : "urn:uuid:54321",
  +                "relatedReferenceUrn" : "urn:uuid:54321",
                   "lastModifiedTimestamp" : 1390607277299,
               }
   
  
positive.code: referenceUrn | String | true | false | Minimum |
  type | String | true | false | Minimum |
  relatedEntityReferenceType | EntityReferenceType | true | false | Minimum |
  relatedReferenceURN | String | true | false | Minimum |
  
  ### Field Notes
  - The `entityReferenceType` and `referenceUrn` fields jointly represent the *owner* or *initiator* of the relationship
  - The `relatedEntityReferenceType` and `relatedReferenceURN` fields jointly represent the *subordinate* member of the relationship
  - The `type` field is available to create an ontology or high level categories that can be used to group related relationships.
  The platform makes no inferences about this case-sensitive field.
  
  
negative.code:             {
                  "type": "Owns",
                  "relatedEntityReferenceType": "Object",
                  "relatedReferenceUrn" : "urn:uuid:54321"
              }
  
  + Response 201 (application/json)
  