Cargo Overhaul - Various Issues

[Arrow768]

Fix various smaller issues with the cargo overhaul before merging

• Shipment Cost (aliquot) in the order overview being displayed when its 0
• Calculate the Shipment Cost (aliquot) for the orders in the shipment once the shuttle has been sent
• Create and store the invoice for the shipment once the shuttle has been sent back to central
• List the shipments somewhere (maybe in the control application)
• Generate a random tracking code for the order (numeric) and display it to the user
• Add a Tracking function to the order application
• Figure out why sometimes the button text is not shown (Submit Button at the Order App, Details Button at the Control App)