Mismatch in the repository example and pub.dev example

The example given on the package [page](https://pub.dev/packages/flutter_p2p/example) does not match the example code mentioned in the [repository](https://github.com/mintware-de/flutter_p2p/blob/master/example/lib/main.dart).
The example on the pub.dev page doesn't work either. It should be updated to reflect the latest, working example.