add HashedModuleIdsPlugin

Author: PanJiaChen

build/webpack.prod.conf.js

@@ -72,6 +72,8 @@ var webpackConfig = merge(baseWebpackConfig, {
             // necessary to consistently work with multiple chunks via CommonsChunkPlugin
             chunksSortMode: 'dependency'
         }),
+        // cache Module Identifiers
+        new webpack.HashedModuleIdsPlugin(),
         // split vendor js into its own file
         new webpack.optimize.CommonsChunkPlugin({
             name: 'vendor',