title: Programatically hiding and showing individual tabs in React Native Router Flux Tabbar
body: <p>I have a tabbar in my app using React Native Router Flux. There are a couple use cases where hiding or showing specific tabs based on the current user would be very helpful. The main ones I have run into are:</p>
  
  <ul>
  <li>AB testing new tabs to specific users</li>
  <li>Showing a special admin tab to certain users with certain privileges</li>
  </ul>
  
  <p>The react-native-router-flux library does not support any options to do this from what I can see. How can I achieve this functionality?</p>