[MM-14058] Add support for i18n (#2190)

* Add language files

* Add react-intl, mmjstool, setup for adding translations

* Translated main module

* Translations for renderer

* A few minor fixes

* More fixes

* Add CI, add missing menu translations, other cleanup

* Added setting to manually select the language of the app

* Force English for E2e

* Unit tests

* Fix mmjstool

* Move set language to before update menu

* PR feedback

src/main/app/initialize.test.js

@@ -39,6 +39,8 @@ jest.mock('electron', () => ({
         setAppUserModelId: jest.fn(),
         getVersion: jest.fn(),
         whenReady: jest.fn(),
+        getLocale: jest.fn(),
+        getLocaleCountryCode: jest.fn(),
     },
     ipcMain: {
         on: jest.fn(),
@@ -54,6 +56,11 @@ jest.mock('electron', () => ({
     },
 }));
 
+jest.mock('main/i18nManager', () => ({
+    localizeMessage: jest.fn(),
+    setLocale: jest.fn(),
+}));
+
 jest.mock('electron-devtools-installer', () => {
     return () => ({
         REACT_DEVELOPER_TOOLS: 'react-developer-tools',