add license section to README.md

README.md

@@ -134,6 +134,10 @@ Wang, G., P. R., Cook, and S. Salazar. 2015. "[ChucK: A Strongly Timed Computer
 ## ChucK Media
 Non-source code documents (papers, logos, soundbites, comics) have been migrated to the [chuck-media](https://github.com/ccrma/chuck-media) repository.
 
+## License
+ChucK is dual-licensed under the [MIT License](https://github.com/ccrma/chuck/blob/main/LICENSE.MIT) and the [GNU General Public License 2.0](https://github.com/ccrma/chuck/blob/main/LICENSE.GPL) (or any later version).
+You can choose either license if you use this work.
+
 ## ChucK Community
 Join us! [ChucK Community Discord](https://discord.gg/ENr3nurrx8) | [ChucK-users Mailing list](https://lists.cs.princeton.edu/mailman/listinfo/chuck-users)