title: Refreshing auth token when call retrofit api with rxandroid
body: <p>I have working retrofit api, which return observable on some data.</p>
  
  <p>Api use auth token for access to server. When auth token expired I have error message about it (Observer call onError in subscriber).</p>
  
  <pre><code>public Observable&lt;MyObject&gt; getObjectObservable() {
      return mApi.getObject();
  }
  </code></pre>
  
  <p>I can refresh token with observable too:</p>
  
  <pre><code>private Observable&lt;AuthResult&gt; restoreToken() {
      return mApi.restoreToken(new RestoreTokenBody(getRestoreToken()));
  }
  </code></pre>
  
  <p>How implement next steps in getObjectObservable function:</p>
  
  <ul>
  <li>First try mApi.getObject()</li>
  <li>On Error refresh token</li>
  <li>After refreshing it call mApi.getObject() again</li>
  </ul>