Changes to Create an order subscription

added the optional property data/relationships/resource_errors to the response with the 201 status

added the new pending enum value to the data/attributes/status response property for the response status 201

added the new required request property data/relationships/market/data

added the new required request property data/relationships/source_order/data

request property data/type was restricted to a list of enum values

removed the request property data/relationships/market/id

removed the request property data/relationships/market/type

removed the request property data/relationships/source_order/id

removed the request property data/relationships/source_order/type

added the new optional request property data/attributes/place_target_order

added the new optional request property data/attributes/renewal_alert_period

added the new optional request property data/relationships/tags

the type request property default value order_subscriptions was removed

added the new order_subscriptions enum value to the request property data/type

added the media type application/vnd.api+json for the response with the status 201