new UglifyJSPlugin({
        include: /\.min\.js$/,
        sourceMap: true,
        uglifyOptions: {
          mangle: {
            ie8: false
          },
          output:{
            comments: saveLicense
          },
          compress: {
            booleans: true,
            comparisons: true,
            conditionals: true,
            dead_code: true,
            drop_console: false,
            evaluate: true,
            hoist_funs: true,
            if_return: true,
            inline: false,
            join_vars: true,
            loops: true,
            pure_getters: true,
            sequences: true,
            side_effects  : true,
            unused: true,
            warnings: false
          }
        }
      })