title: swipeEnabled is not working in TabNavigator for swipe disable
body: <p>I want to disable swipe for tab change in TabNavigator.
  I have found two solutions</p>
  
  <p>1) <code>swipeEnabled: false,</code></p>
  
  <p>2) <code>navigationOptions: {
        gesturesEnabled: false
      }</code></p>
  
  <p>both are not working in iOS in react-native.
  Any solution will be helpful.</p>