title: react navigation two navigators on one screen nested in StackNavigator
body: <p>I got one screen where I need to get <code>createMaterialTopTabNavigator</code> and <code>createBottomTabNavigator</code> it is nested in <code>createStackNavigator</code>. </p>
  
  <p>So I click on button on HomeScreen and StackNavigator navigates me to screen where is 
  <code>createBottomTabNavigator</code> primary navigation and <code>createMaterialTopTabNavigator</code> is different for each screen in <code>createBottomTabNavigator</code></p>
  
  <p>So it should be </p>
  
  <pre><code>createStackNavigator
      createBottomTabNavigator
          createMaterialTopTabNavigator
             SomeTabBarScreen
             SomeTabBarScreen
          createMaterialTopTabNavigator //if I click on icon in BottomNavigator to navigate on another screen I want different TopNavigator
             SomeTabBarScreen
             SomeTabBarScreen
  </code></pre>