add scanner class update cart class
delete inventory class set,getCartItemsText() add cart class getCartItemsText()
add Cart class getgetPromotionPrice()
delete inventory class set,getPromotionPrice()
add cart class getPromotionsText() delete inventory class set,getPromotionsText()
delete inventory class set,getPromotionsText()
add cart class getTotalPrices()
delete inventory set,getTotalPrices()
update setInventory() as toString()
update cart class addCartItem()`s parameter
uodate getCartItemsText() and add CartItem class getPaymentCount(),getSubtotal(),toInventoryText()
update printInventory()