title: React Router v4 - How to get current route?
body: <p>I'd like to display a <code>title</code> in <code>&lt;AppBar /&gt;</code> that is somehow passed in from the current route. </p>
  
  <p>In React Router v4, how would <code>&lt;AppBar /&gt;</code> be able to get the current route passed into it's <code>title</code> prop? </p>
  
  <pre><code>  &lt;Router basename='/app'&gt;
      &lt;main&gt;
        &lt;Menu active={menu} close={this.closeMenu} /&gt;
        &lt;Overlay active={menu} onClick={this.closeMenu} /&gt;
        &lt;AppBar handleMenuIcon={this.handleMenuIcon} title='Test' /&gt;
        &lt;Route path='/customers' component={Customers} /&gt;
      &lt;/main&gt;
    &lt;/Router&gt;
  </code></pre>
  
  <p>Is there a way to pass a custom title from a custom <code>prop</code> on <code>&lt;Route /&gt;</code>?</p>