Documentation: ScreeningPackageOrder

This is a subset of the full ScreeningOrder. It is intended to support an "OrderByPackageID" scenario. As the name implies, the "order by package" pattern involves bundling all screening service options within predefined packages that are known to the customer and to the screening provider. This enables services to be ordered simply by referencing an associated "PackageID." When using this pattern, details about specific screening services do not have to be communicated within the order. This simplifies order creation significantly and provides the opportunity to use an interoperable subset of the full ScreeningOrder noun.