Update relationships with resource

[pixelhandler]

In addition to persisting relationship changes separately from PATCH'ing a resource's attribute(s) by using the the service (adapter) methods mentioned above, the updateResource has an optional second parameter includeRelationships to provide an array with a list of relationship names that should be PATCH'd using the resource's link (endpoint). This optional argument, provides a way to update attributes and/or relationships together using the main endpoint for the resource.

For example to update the relationships with any changed attributes for a resource use: service.updateResource(resource, ['author', 'comments']) (where service is the injected service for the resource instance.

• Add relationship change tracking to the Resource
• Add rollbackRelationships method
• Change rollback to call both rollbackAttributes and rollbackRelationships
• Add changedRelationships property and relationMetadata method to Resource
• Add new relationship serialization methods
• Add optional second parameter includeRelationships to ApplicationAdapter#updateResource method to patch relationships
  • Opt into what relationships to patch using an array of the relationships (names, e.g. ['author', 'comments']