[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/common/config/index.ts

@@ -328,6 +328,10 @@ export class Config extends EventEmitter {
         return this.combinedData?.autoCheckForUpdates;
     }
 
+    get appLanguage() {
+        return this.combinedData?.appLanguage;
+    }
+
     // initialization/processing methods
 
     /**