Changes to Cart simulation

added the new optional request property allowedOutdatedData

the request property items/items/id became required

the request property items/items/quantity became required

the request property items/items/seller became required

the items/items/priceTags/items/rawValue response's property type changed from integer to number for status 200

removed the optional property items/items/priceTags/items/owner from the response with the 200 status