GV-148: customise the shipping module. reorganised and renamed some of the classes to be more consistent and meaningful. added weight range and quantity range
GV-148: revised ShippingMatrixConfig first working version. will take more functionality into their own classes and simplify the ShippingMatrixConfig.
GV-148: finished taking functions out of the shipping modifier and simplified the flow
added function to get all shippingzones if no default zone is found.