title: webpack3 jshint-loader does not work
body: <p>I'm trying to follow this instruction <a href="https://webpack.js.org/loaders/jshint-loader/" rel="noreferrer">https://webpack.js.org/loaders/jshint-loader/</a>
  and get an error:</p>
  
  <p>My config file: </p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>const path = require('path');
  
      module.exports = {
        entry: {
          app: './index.js'
        },
        output: {
          filename: 'bundle.js',
          path: path.resolve(__dirname, 'dist')
        },
  
        module: {
          rules: [
            {
              test: /\.js$/, // include .js files
              enforce: "pre", // preload the jshint loader
              exclude: /node_modules/, // exclude any and all files in the node_modules folder
              use: [
                {
                  loader: "jshint-loader"
                }
              ]
            }
          ]
        },
  
        // more options in the optional jshint object
        jshint: {
          // any jshint option http://www.jshint.com/docs/options/
          // i. e.
          camelcase: true,
  
          // jshint errors are displayed by default as warnings
          // set emitErrors to true to display them as errors
          emitErrors: false,
  
           // jshint to not interrupt the compilation
           // if you want any file with jshint errors to fail
           // set failOnHint to true
           failOnHint: false,
  
           // custom reporter function
           reporter: function(errors) { }
         }
      };</code></pre>
  </div>
  </div>
  </p>
  
  <p>error text: </p>
  
  <blockquote>
    <p>Invalid configuration object. Webpack has been initialised using a configuration object that does not match the API schema.
     - configuration has an unknown property 'jshint'. These properties are valid:
       object { amd?, bail?, cache?, context?, dependencies?, devServer?, devtool?, entry, externals?, loader?, module?, name?, node?, output?, performance?, plugins?, prof
    ile?, recordsInputPath?, recordsOutputPath?, recordsPath?, resolve?, resolveLoader?, stats?, target?, watch?, watchOptions? }
       For typos: please correct them.
       For loader options: webpack 2 no longer allows custom properties in configuration.</p>
  </blockquote>