Resetting the app after deletion and cleanup settings (#372)

* Fixes #361 - Reset everything if the app has been deleted since the last run

* Cleaned up and renamed the ElementSettings to ApplicationSettings. Removed its singleton and moved it to the service locator.

* Moved the ApplicationSettings to the Application folder

* Merged together the BuildSettings and ApplicationSettings

* Reset the UserDefaults too when resetting the application state

* Rename ServiceLocator.applicationSettings to just settings

* Fix indentation

* Rename ApplicationSettings to AppSettings

* Various tweaks following code review

* Fix unit tests

ElementX/Sources/UITests/UITestsAppCoordinator.swift

@@ -28,6 +28,10 @@ class UITestsAppCoordinator: AppCoordinatorProtocol {
         mockScreens = UITestScreenIdentifier.allCases.map { MockScreen(id: $0, navigationRootCoordinator: navigationRootCoordinator) }
         
         ServiceLocator.shared.register(userNotificationController: MockUserNotificationController())
+        
+        AppSettings.configureWithSuiteName("io.element.elementx.uitests")
+        AppSettings.reset()
+        ServiceLocator.shared.register(appSettings: AppSettings())
     }
     
     func start() {