Cart updates prices, taxes etc. on every update

Before, the cart decided, based on the update actions, whether to update the product prices and tax rates. We've received feedback that this was unpredictable and confusing.

Therefore, the cart now updates the product prices and tax rates, along with discounts and the shipping info, on every update. No change to your code is necessary, but you may remove superfluous Recalculate update actions (if they don't update the product data).

• [API] The Update Cart section now contains a description of the updates
• [API] The description of the Recalculate update action has been changed to reflect the two remaining use cases for it