V2/Northwind not conforming to OData V2 specification if `$top` is included due to missing `"results"`

[boghyon]

Similar to the issue #119, the reference service Northwind does currently not comply with the OData V2 specification if the request URL contains the system query option $top.

• Bad example: https://services.odata.org/V2/Northwind/Northwind.svc/Products?$format=json&$top=2
  See that the response starts with {"d":[ without the "results". The specification, however, mandates to respond with the "results" property if a collection is requested. See the topic "2.2.6.3.2 Entity Set (as a JSON Array)" on page 101.

• Good example: https://services.odata.org/V2/Northwind/Northwind.svc/Products?$format=json&$skip=2
  See that the response starts correctly with {"d":"results":[ if the $top is not included in the URL.

[boghyon]

@ralfhandl @mikepizzo Could you confirm whether the "results" property is a MUST in the above case with $top? Or is it optional? V2 sample services by SAP do include the "results" property even with $top expectedly.

[ralfhandl]

That's surprising behavior. The query options $top and $skip should just change the included entities and not change the response shape.