add locale.rake

Author: JasonYCHuang

lib/tasks/locale.rake

@@ -0,0 +1,8 @@
+require "react_on_rails/locales_to_js"
+
+namespace :react_on_rails do
+  desc "Generate i18n javascript files"
+  task locale: :environment do
+    ReactOnRails::LocalesToJs.new
+  end
+end