Added README footer

Author: toonvandenbos

README.md

@@ -94,3 +94,17 @@ $date = Timezone::store(new Carbon('2023-01-01 00:00:00', 'Europe/Brussels'));
 // Alternatively, set the storage timezone yourself:
 $date = (new Carbon('2023-01-01 00:00:00', 'Europe/Brussels'))->setTimezone(Timezone::storage());
 ```
+## 🔥 Sponsorships 
+
+If you are reliant on this package in your production applications, consider [sponsoring us](https://github.com/sponsors/whitecube)! It is the best way to help us keep doing what we love to do: making great open source software.
+
+## Contributing
+
+Feel free to suggest changes, ask for new features or fix bugs yourself. We're sure there are still a lot of improvements that could be made, and we would be very happy to merge useful pull requests. Thanks!
+
+## Made with ❤️ for open source
+
+At [Whitecube](https://www.whitecube.be) we use a lot of open source software as part of our daily work.
+So when we have an opportunity to give something back, we're super excited!
+
+We hope you will enjoy this small contribution from us and would love to [hear from you](mailto:hello@whitecube.be) if you find it useful in your projects. Follow us on [Twitter](https://twitter.com/whitecube_be) for more updates!