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/Screens/Settings/View/SettingsScreen.swift

@@ -19,7 +19,7 @@ import SwiftUI
 struct SettingsScreen: View {
     @State private var showingLogoutConfirmation = false
     @Environment(\.colorScheme) private var colorScheme
-    @ObservedObject private var settings = ElementSettings.shared
+    @ObservedObject private var settings = ServiceLocator.shared.settings
 
     @ScaledMetric private var avatarSize = AvatarSize.user(on: .settings).value
     @ScaledMetric private var menuIconSize = 30.0
@@ -110,30 +110,20 @@ struct SettingsScreen: View {
             .listRowSeparator(.hidden)
             .foregroundColor(.element.primaryContent)
             .accessibilityIdentifier("reportBugButton")
-
-            if BuildSettings.settingsCrashButtonVisible {
-                Button("Crash app",
-                       role: .destructive) { context.send(viewAction: .crash)
-                }
-                .listRowInsets(listRowInsets)
-                .accessibilityIdentifier("crashButton")
-            }
         }
     }
 
     @ViewBuilder
     private var userInterfaceSection: some View {
-        if BuildSettings.settingsShowTimelineStyle {
-            Section {
-                Picker(ElementL10n.settingsTimelineStyle, selection: $settings.timelineStyle) {
-                    ForEach(TimelineStyle.allCases, id: \.self) { style in
-                        Text(style.description)
-                            .tag(style)
-                    }
+        Section {
+            Picker(ElementL10n.settingsTimelineStyle, selection: $settings.timelineStyle) {
+                ForEach(TimelineStyle.allCases, id: \.self) { style in
+                    Text(style.description)
+                        .tag(style)
                 }
-                .listRowInsets(listRowInsets)
-                .accessibilityIdentifier("timelineStylePicker")
             }
+            .listRowInsets(listRowInsets)
+            .accessibilityIdentifier("timelineStylePicker")
         }
     }