Controller Support: Seperate the player inventory screen from the barter/loot screen

Currently when performing barter/loot the inventory and barter/loot menu are still on the same page. This causes the GUIs to be more clunky, especially when using GUI scaling. To add better parity with the xbox GUI these menus should be separated into different screens. When in the inventory the barter/loot should not be visible, and vice versa, when in the barter/loot the inventory should not be visible.

This will not only be more aesthetically pleasing, but could make these menus easier to navigate.