change support button to settings button

and add new empty settings drawer

src/actions/app.ts

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-// Copyright (c) 2020 The Pybricks Authors
+// Copyright (c) 2020-2021 The Pybricks Authors
 // File: actions/app.ts
 // Actions for the app in general.
 
@@ -9,6 +9,10 @@ import { Action } from 'redux';
 export enum AppActionType {
     /** The app has just ben started. */
     Startup = 'app.action.startup',
+    /** Open settings dialog. */
+    OpenSettings = 'app.action.openSettings',
+    /** Close settings dialog. */
+    CloseSettings = 'app.action.closeSettings',
     /** Toggle documentation visibility. */
     ToggleDocs = 'app.action.toggleDocs',
 }
@@ -21,6 +25,22 @@ export function startup(): AppStartupAction {
     return { type: AppActionType.Startup };
 }
 
+/** Action to open the settings dialog. */
+export type AppOpenSettingsAction = Action<AppActionType.OpenSettings>;
+
+/** Creates an action to open the settings dialog. */
+export function openSettings(): AppOpenSettingsAction {
+    return { type: AppActionType.OpenSettings };
+}
+
+/** Action to close the settings dialog. */
+export type AppCloseSettingsAction = Action<AppActionType.CloseSettings>;
+
+/** Creates an action to close the settings dialog. */
+export function closeSettings(): AppCloseSettingsAction {
+    return { type: AppActionType.CloseSettings };
+}
+
 /** Action to toggle documentation visibility. */
 export type AppToggleDocsAction = Action<AppActionType.ToggleDocs>;
 
@@ -30,4 +50,8 @@ export function toggleDocs(): AppToggleDocsAction {
 }
 
 /** common type for all app actions. */
-export type AppAction = AppStartupAction | AppToggleDocsAction;
+export type AppAction =
+    | AppStartupAction
+    | AppOpenSettingsAction
+    | AppCloseSettingsAction
+    | AppToggleDocsAction;