title: HMR isn't working after moving files to /app folder
body: <p>Hi I'm currently trying to learn how to use express along with webpacks HMR, and every time I update and save a file it gives me the error:</p>
  
  <p>"The following modules couldn't be hot updated: (Full reload needed)"
  "./app/components/App.js"</p>
  
  <p>Is there something wrong with my current config files?</p>
  
  <p>So I have a directory structure like this:</p>
  
  <pre><code>todos
      |
      app
        |
      package.son
      server.js
      webpack.config.js
  </code></pre>
  
  <p>and I have a webpack.config.js file and a server.js file that looks like the following:</p>
  
  <pre><code>var path = require('path');
  var webpack = require('webpack');
  
  
  module.exports = {
    context: path.join(__dirname + "/app"),
  
    entry: ['./index'],
    output: {
      path: "/bundle",
      publicPath: '/static/',
      filename: "bundle.js"
    },
    module: {
      loaders: [
       {
          test: /\.jsx?$/,
          exclude: /(node_modules|bower_components)/,
          loader: 'babel',
          query: {
            presets: ['react', 'es2015']
          }
        }
      ]
    },
    resolve: {
      extensions: ['', '.js', '.jsx']
    }
  
  };
  </code></pre>
  
  <p>server.js</p>
  
  <pre><code>var webpack = require('webpack')
  var webpackDevMiddleware = require('webpack-dev-middleware')
  var webpackHotMiddleware = require('webpack-hot-middleware')
  var config = require('./webpack.config')
  
  var app = new (require('express'))()
  var port = 3000
  
  var compiler = webpack(config)
  app.use(webpackDevMiddleware(compiler, { noInfo: true, publicPath: config.output.publicPath }))
  app.use(webpackHotMiddleware(compiler))
  
  app.get("/", function(req, res) {
    res.sendFile(__dirname + '/app/index.html')
  })
  
  app.listen(port, function(error) {
    if (error) {
      console.error(error)
    } else {
      console.info("==&gt;   Listening on port %s. Open up http://localhost:%s/ in your browser.", port, port)
    }
  })
  </code></pre>