fixed example

example/scripts/postinstall.js

 const cp = require('child_process');
 cp.execSync(`rm -rf node_modules/react-native-navigation/node_modules`);
 cp.execSync(`rm -rf node_modules/react-native-navigation/example `);
-cp.execSync(`rm -rf yarn.lock`);

example/src/screens/PushedScreen.js

   onResetToPress() {
     this.props.navigator.resetTo({
       title: "New Root",
-      screen: "example.ThirdTabScreen"
+      screen: "example.StyledScreen",
+      animated: true
     });
   }
 }