What:
- new method `previewOrderChange`
- Calculate all the actions related to an order change.
- Return the preview of the final Order, with all the calculated values.
- Associate actions with items and shipping_methods they modified.
FIXES: CORE-2509
We are adding tax inclusive pricing calculation when listing products.
Two things to keep in mind:
- `region_id` will be required if you request calculated prices.
- We won't accept `currency_code` anymore, as that will come from the region info (since ultimately a cart and its currency are tied to a region)
REF CORE-2376
DEPENDS ON #8003
Carlos R. L. Rodrigues
Stevche Radevski
Adrien de Peretti