Implement manual initialzation for Angular app

Manual initialization allows for some asynchronous work to
finish ahead of Angular's startup. The initial motivation is
to be able to guarantee translation files have been fetched
before rendering content that needs translation. If a locale
isn't supported or if the request to get a json file fails,
the i18n service falls back to en.

Signed-off-by: gconsidine <gconsidi@redhat.com>

awx/ui/build/webpack.base.js

@@ -109,7 +109,7 @@ const base = {
             jsonlint: 'codemirror.jsonlint'
         }),
         new ExtractTextPlugin('css/[name].[chunkhash].css'),
-        new CleanWebpackPlugin([STATIC_PATH, COVERAGE_PATH, LANGUAGES_PATH], {
+        new CleanWebpackPlugin([STATIC_PATH, COVERAGE_PATH], {
             root: UI_PATH,
             verbose: false
         }),