Draft: Cleaning status bar feature + Refactoring HUD

This MR contains:

• Removal of ThemeFeature that wasn't used
• Creation of a StatusBarFeature which contains a refactor of the old ThemeFeature.
• Refactor of HUDFeature

Sources/App/AppDelegate.swift

@@ -11,8 +11,9 @@ import CrashReporting
 import PushNotifications
 import DependencyInjection
 
-import OnboardingFeature
 import DropboxFeature
+import StatusBarFeature
+import OnboardingFeature
 
 let logger = Logger(subsystem: "logs_xxmessenger", category: "AppDelegate.swift")
 
@@ -60,7 +61,7 @@ public class AppDelegate: UIResponder, UIApplicationDelegate {
             )
         )
 
-        window = Window()
+        window = UIWindow()
         window?.rootViewController = rootScreen
         window?.backgroundColor = UIColor.white
         window?.makeKeyAndVisible()