Update orders totals on add to cart.
Update orders totals on add to cart.

When a gift card was added to the cart, there was a state which could
occur in Spree 2.2 where the order total was not correct.

Calling order.update_totals ensures that the total is correct.

mr-ado/spree_gift_card,JDutil/spree_gift_card,JDutil/spree_gift_card,mr-ado/spree_gift_card,mr-ado/spree_gift_card,Boomkat/spree_gift_card,JDutil/spree_gift_card,Boomkat/spree_gift_card,Boomkat/spree_gift_card