Mall update

The September 2013 Mall update replaced manage.php with a revamped backoffice.php. Items are now added one item at a time.

Changes in my branch:

Replaced the AddItemsToStoreRequest.py with a single item version since the new interface only allows one item at a time. Items can now be pulled directly from Hangk's and placed into your store.
Updated the StoreInventoryRequest to use backoffice.php
Added MallItemPriceSearchRequest.py which can search for the lowest prices in mall for both unlimited and limited stores
Added StoreUpdateItemRequest.py which lets you update price and limit for an item in your mall store.
This is my first time using Git, so let me know if I need to change or update anything in this issue ticket.