title: file-loader is not coping images
body: <p>I am making the transition from gulp to webpack and I have images in a <code>static/img</code> folder that I want to process with <code>image-webpack-loader</code> and then copy to a <code>build/public/img</code> folder.  Is <code>file-loader</code> what I want to use for this?  The problem is that the images are not being copied.  In fact it seems like this loader is being ignored during the build.</p>
  
  <pre><code>const ExtractTextPlugin = require('extract-text-webpack-plugin');
  const path = require('path');
  
  module.exports = {
    context: path.resolve(__dirname, 'static'),
    entry: ['./js/frontend.js','./sass/app.scss'],
    output: {
      path: path.join(__dirname, 'build/public'),
      filename: 'js/frontend.js'
    },
    module: {
      rules: [
        {
          test: /\.(jpe?g|png|gif|svg)$/,
          loader: [
              'file-loader?name=img/[name].[ext]',
              'image-webpack-loader?bypassOnDebug&amp;optimizationLevel=7&amp;interlaced=false'
          ]
        },
        {
          test: /\.(sass|scss)$/,
          loader: ExtractTextPlugin.extract({
            use: [{
              loader: 'css-loader',
              options: {
                sourceMap: true
              }
            },
            {
              loader: 'sass-loader',
              options: {
                sourceMap: true
              }
            }]
          })
        }
      ]
    },
    plugins: [
      new ExtractTextPlugin({ 
        filename: 'css/styles.css',
        allChunks: true
      })
    ],
    devtool: 'source-map'
  };
  </code></pre>