add_engine_locales

# File railties/lib/rails/plugin/loader.rb, line 88
        def add_engine_locales
          # reverse it such that the last engine can overwrite translations from the first, like with routes
          locale_files = engines.select(&:localized?).collect(&:locale_files).reverse.flatten
          I18n.load_path += locale_files - I18n.load_path
        end