Struts action class that corresponds to the main administrator view panel for
order items. Used for requests to "/administrator/OrderItem.do".
The execute method of this class populates a
Collection named itemCollection in the request
scope containing the items to be displayed. Next, it sets a request scope
variable named editPermission that determines if the current
user has permission to edit the items. Finally, it creates a
Collection named breadcrumbs containing the
links and labels of each breadcrumb for display.