Set parents during the cache process

Doing:

```js
return this.request(options).then(function(results) {
      results.forEach(function(result) {
        result.setProperties(parents);
      });
      return results;
    });
```

We're only setting `parents` for objects previously cached, ignoring the new ones.

Reusing `processingOptions`, this is being used now to set also `parents`, which will be added to the response at the `ajaxAndUpdateCache` method.

cc @JackCA @jclem