Use react-native link for installation

[buckhx]

Would make the installation process much easier, check the airbnb react-native-maps process. Realm uses it as well.

https://github.com/airbnb/react-native-maps/blob/master/docs/installation.md

https://facebook.github.io/react-native/docs/linking-libraries-ios.html

[andpor]

Contributions are welcome. Can you prepare a PR ?