* Fix up tests in the product/* folder.
* Handle data store updates for grouped, variable, external, simple, and general data store updates for products.
* Variations & variable changes.
* Update -functions.php calls to use data store.
* Add an interface for the public product data store methods.
* Finished product factory tests
* Correctly delete in the api, fix up some comments, and implement an interface for the public variable methods.
* Fix up delete in all versions of the api
* Handle feedback
* Match protected decloration to parent
Claudio Sanches
Mike Jolley
Justin Shreve