Obtain retail price and sale price from products

Altered the recursive price functionality to allow access to obtaining the retail price from the product uom's. I have a case of wanting to offer a discount to the retail price which is setup by setting the retail field in the catalog_product_uom table to a different value to the price field. This funcaitonlity allows access to obtaining either the retail price or the actual sale price (default functionality is to obtain the price for backwards compatibility) This is achieved by passing a $retailPrice boolean through the recusrive price functionality so when UOM prices are obtained it gets the price if $retailPrice if false (default) or retail if $retailPrice is true.