Major Added new methods, simple (default) and line, to calculate totals for carts and orders.
Minor Fixed a bug where a PUT to a cart item with a quantity of 0 would return a 404.
Minor Fixed a bug where passing mismatched IDs in the URL and body, or not passing an ID in the body would cause a 5xx error.
Minor You can now add a tax item at the same time you add a cart item. See Add Product to Cart or Add Custom Item to Cart and for tax item reference see Tax Items.