Inventory. Collapsible Results Pane

Purpose: Implement the general pattern with the ability to collapse the results list pane in the Inventory app, and maximize the view of the detailed instance record, and the catalogers can focus on just the Instance detailed record, with associated holdings and items. When the catalogers want to get back the search result list (= 2nd pane) then the detailed view can be unmaximize again.

See: STCOM-114, STCOM-194