title: How extract css files for old IE
body: <p>My project environment is</p>
  
  <pre><code>webpack 1.15.0
  extract-text-webpack-plugin 1.0.1
  </code></pre>
  
  <p>I extract the styles into a single css file, and it works well in chrome firefox and IE10+, but not in IE9-.</p>
  
  <p>I have find that the old IE have limits for css file: </p>
  
  <pre><code>A sheet may contain up to 4095 rules(maybe selectors)
  A sheet may @import up to 31 sheets
  @import nesting supports up to 4 levels deep
  </code></pre>
  
  <p>but my extracted css file have 4095+ selectors.</p>
  
  <p>So, is there a way to split the extracted css file by a limit function automatically? like :</p>
  
  <pre><code>var ExtractTextPlugin = require("extract-text-webpack-plugin");
  module.exports = {
      module: {
          loaders: [
              { 
                test: /\.css$/, 
                loader: ExtractTextPlugin.extract("style-loader", "css-loader") 
              }
          ]
      },
      plugins: [
          new ExtractTextPlugin("styles.css",{
             // options callback -- how to handle the extracted result
             callback: function(extractedResult){
                // some limit api that the extractedResult can be split into pieces
             }
          })
      ]
  }
  </code></pre>