Full Package v1.1 ...

Added error checking so when a customer enters an invalid or out-of-stock item #, a message will display in their shopping cart letting them know. Also, when an item has attribute(s), instead of just redirecting to the prod page and leaving the customer clueless, a message now appears asking them to choose an option (this also works with the "buy now" buttons in product listings).

More screenshots included.

NOTE: THIS DOES NOT INCLUDE THE "DISABLE CART" CONTRIB CHANGES FROM PREVIOUS POST!

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