i18n string dictionaries (#3532)

* TabBar & Settings -> Views i18n enabled

* Proxy i18n

* Settings i18n

* defaultLocale

* Introduce thin Translate wrapper

* PropTypes util caters for multiples

* Translate & LanguageSelector under ui

* Update location & proptypes

* Add UI Language selector

* German settings pages

* Add German language selection

* Corrected umlaut encoding

* Lint

* Re-apply pre-merge conflict changes

* better German i18n

* Language names in locale language

* i8n -> index

* Allow for development/production operation

* Use Yahoo react-intl (as opposed to react-i18nify)

* Use default messages wih expansions

* Remove non-reused variable definitions

* Use FormattedMessage directly, opens up WebPack & Babel opportunities

* Add flat to flatten

* Extract default messages via babel

* Webpack to aggegrate i18n defaultMessage

* Re-add react-intl after merge

* Update proptype references (merge)

* Strip down external dictionary

* i18n for dapps

* Restore tests submodule

* Allow language changes to reflect

* Style updates

js/webpack/app.js

@@ -17,6 +17,7 @@
 
 const webpack = require('webpack');
 const path = require('path');
+const ReactIntlAggregatePlugin = require('react-intl-aggregate-webpack-plugin');
 const WebpackErrorNotificationPlugin = require('webpack-error-notification');
 const CopyWebpackPlugin = require('copy-webpack-plugin');
 const HtmlWebpackPlugin = require('html-webpack-plugin');
@@ -163,7 +164,15 @@ module.exports = {
     }));
 
     if (!isProd) {
+      const DEST_I18N = path.join(__dirname, '..', DEST, 'i18n');
+
       plugins.push(
+        new ReactIntlAggregatePlugin({
+          messagesPattern: DEST_I18N + '/src/**/*.json',
+          aggregateOutputDir: DEST_I18N + '/i18n/',
+          aggregateFilename: 'en'
+        }),
+
         new webpack.optimize.CommonsChunkPlugin({
           filename: 'commons.[hash:10].js',
           name: 'commons',