Expose endpoint to UPDATE IN

[AllanEgebjerg]

Working with TR orders in the API, we are looking for a way to perform the "Update IN" on a shipment, that is possible from the shipment window (W(10002)))

or alternatively from the from the Process Shipments window: 

To make TR orderflow work from external system (WMS) we would need to be able to UPDATE IN on a TR shipment from the webapi.