Add some docs

packages/shared/i18n/index.ts

@@ -3,16 +3,30 @@ import { initReactI18next } from 'react-i18next';
 import Backend from 'i18next-http-backend';
 import { getBestPossibleUserLocale } from './utils';
 
+/**
+ * Load translations.
+ *
+ * Localization and related concerns (aka "internationalization", or "i18n") for
+ * our apps is handled by i18n framework.
+ *
+ * In addition to the base i18next package, we use two of its plugins:
+ *
+ * - i18next-http-backend, for loading the JSON files containin the translations
+ *   at runtime, and
+ *
+ * - react-i18next, which adds React specific APIs
+ */
 export const setupI18n = async () => {
+    // https://www.i18next.com/overview/api
     await i18n
-        // i18next-http-backend
-        // loads translations from your server
-        // https://github.com/i18next/i18next-http-backend,
+        // i18next-http-backend: Asynchronously loads translations over HTTP
+        // https://github.com/i18next/i18next-http-backend
         .use(Backend)
-        // pass the i18n instance to react-i18next.
+        // react-i18next: React support
+        // Pass the i18n instance to react-i18next.
         .use(initReactI18next)
-        // init i18next
-        // for all options read: https://www.i18next.com/overview/configuration-options
+        // Initialize i18next
+        // Option docs: https://www.i18next.com/overview/configuration-options
         .init({
             returnEmptyString: false,
             fallbackLng: 'en',