title: Extract React Router state in URL
body: <p>I'm using react-router and redux-simple-router in conjunction with server side rendering and when I navigate to a url like: </p>
  
  <pre><code>routeActions.push({ pathname: '/main', state: 'some_state'});
  </code></pre>
  
  <p>I want to be able to extract <code>some_state</code> from the request so I can render an initial redux state and send that back to the client. How do I extract the state from the request on the server side? Where does history and react-router put it?</p>
  
  <p>This is particularly important for mobile because desktop, as I've tested, doesn't fire separate requests but mobile devices do which means the page reloads with a fresh initial state.</p>