title: Integrating ActionCable with Webpacker in Rails 5.1
body: <p>I am upgrading my app from Rails 5.0 to 5.1, and there is one thing I can't find being mentioned anywhere - usage of Webpacker to process ActionCable JavaScript files.</p>
  
  <p>I realise that Webpacker and the asset pipeline are supposed to work side by side, but now that we have Webpack build into Rails it would be a waste not to use it for files located in <code>assets</code> directory (which is where ActionCable lives), yet I can't find any information on how to do that.</p>
  
  <p>I'm specifically interested in Babel, so I could use ES6. Any ideas?</p>