title: Go back to root navigator from a nested TabNavigator
body: <p>This is how my hierachy looks,</p>
  
  <pre><code>-StackNavigator (root)
      -Portada
      -MainScreen (TabNavigator)
          -Home
          -Cronograma
          -Perfil
      -Login
      -Register
  </code></pre>
  
  <p>I navigate to Portada -> Main Screen -> Perfil,
  Now I want to go back from Perfil to Portada again how I can do it?</p>