loaders.js

module: {
    preLoaders: [
      {
        test: /\.js$/,
        exclude: [
          /node_modules/,
          /build/
        ],
        loader: "eslint-loader"
      }
    ],
    loaders: [
      {
        test: /\.(svg)$/,
        loader: 'raw-loader'
      },
      {
        test: /\.js$/,
        exclude: /node_modules/,
        loader: 'babel-loader'
      },
      {
        test:   /\.css$/,
        exclude: /node_modules/,
        loader: ExtractTextPlugin.extract("style-loader", "css-loader!cssnext-loader")
      },
      {
        test: /\.test\/tests.js$/,
        exclude: /node_modules/,
        loaders: ['babel-loader', 'mocha-loader']
      }
    ]
  }