Batch messages / multiple changes

[arneee]

Hi,

according to the API reference, "changes" is an array. Could there be more than one change in a webhook call? For example if there are a lot of notifications, Facebook batches them in other webhooks:

https://developers.facebook.com/docs/graph-api/webhooks/getting-started#validate-payloads

"Event Notifications are aggregated and sent in a batch with a maximum of 1000 updates. However batching cannot be guaranteed so be sure to adjust your servers to handle each Webhook individually."

In the NotificationFactory, only the first entry is used, the rest seems to be discarded.

Would it make sense to loop through the array and make the read() method returning an array of Notification objects, even if it's probably just one on the regular case?

Or an additional readAll() / readBatch() method?

Thanks!

[arneee]

Created PR: #132