Add cart links to the affiliate generated link

Through a form alter (attached) I have added a field to the product form so that the admin can set up a destination that they want the affiliate link to use. I have submitted a patch (following the format given I put issue #5 on it) for the affiliate module that checks the uc_products table for a value in this field. If there is a value it uses cart links to add the product to the cart and then go to the destination given (directly to the checkout for example). I also added a line to format the price of the product for the link as currency.