docs: Update co-contributors with GitHub usernames (#18)

* docs: Update co-contributors with GitHub usernames

* docs: Use GitHub links for co-contributors and improve order

* docs: Change to Contributors and use personal homepage

* docs: Specify core contributors and welcome new contributors

Author: andylizf

README.md

@@ -575,8 +575,11 @@ MIT License - see [LICENSE](LICENSE) for details.
 
 ## 🙏 Acknowledgments
 
-This work is done at [**Berkeley Sky Computing Lab**](https://sky.cs.berkeley.edu/).
+Core Contributors: [Yichuan Wang](https://yichuan-w.github.io/) & [Zhifei Li](https://github.com/andylizf).
 
+We welcome more contributors! Feel free to open issues or submit PRs.
+
+This work is done at [**Berkeley Sky Computing Lab**](https://sky.cs.berkeley.edu/).
 
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