#1 Ability to specify fixed shipping costs

[Michael Kmiec]

Rather than just relying on UPS and FedEx and the
dynamic shipping cost generation, add a way to
introduce fixed shipping costs. Rules:

1.) Fixed information stored in DB.
2.) Administrative interface.
3.) Cost on a per-shipment or per-item basis?
4.) Mutually exclusive methods.
5.) Flag in config to determine.