[BarrelApp]: Add themed controls (mainly OEHUDAlert for now)
[BarrelApp Project]: Added references for UI graphics in the project
[Barrel Project]: Removed an obsolete group from the project
[OEHUDAlert]: Refactored the setPopupButtonItems method to accept string items instead of objects
[BLAppDelegate]: Added OEHUDAlerts for choosing the game's executable after the setup