Deliveries

Deliveries: what a sale grants, per gateway product.

2 operations.

Operation	Summary
`GET /third/delivery`	List deliveries of a gateway
`POST /third/delivery`	Create or extend a delivery

List the access entries of a student from a sale GET

Lists the access entries of a student that came from a sale or subscription ID at the gateway.

List deliveries of a gateway GET

Lists the deliveries of a gateway and sale type, with the school domain and the postback URL to configure at the gateway.