Minor cleanup of files as identified by merging with the ZC 1.5.3. equivalent.
Update the checkout_shipping and shopping_cart pages to
handle mixed attribute calculation for products with attributes
that are not tracked by SBA. (Restore base ZC functionality)
Corrected some installation issues... And incorrect coding.
Refined count of items in customer_basket_review to just the one
customer, not all items that exist in the datatable.