Better error messages when importing orders (api)
Set up attributes for successful order import

Conflicts:
	api/app/controllers/spree/api/orders_controller.rb
	api/spec/controllers/spree/api/orders_controller_spec.rb
Fix conflict after gem money 6.0.0 release

This would bring #2737 back but we need to be able to bundle and
activemerchant current release require money < 6.0.0