[Storefront] Clean up data structures and create a better, more usable Inventory class

[GoogleCodeExporter]

- the tree structure of categories should be hidden and unexposed when
retrieving categories and products from the Inventory class.
- the use of a root category is sort of an implementation detail and should
not be exposed to users of the Inventory class.
- the current Inventory interface does not make it easy enough for
retrieving products and categories
- Inventory should perhaps be made an interface, and have an InventoryImpl
class implement it

Original issue reported on code.google.com by tony.lo...@gmail.com on 12 Dec 2007 at 2:43

[GoogleCodeExporter]

[deleted comment]

[GoogleCodeExporter]

Making as fixed.

Tree structure is now not exposed when using the Inventory class. The root 
category
is removed and replaced with a collection of top-level categories. Retrieving
products and categories from an inventory has been made easier.

Original comment by tony.lo...@gmail.com on 20 Dec 2007 at 1:38

• Changed state: Fixed