CONTRIBUTING.md in chartkick-3.0.2 vs CONTRIBUTING.md in chartkick-3.1.0

- old
+ new

@@ -31,9 +31,10 @@
 
 ## Pull Requests
 
 Fork the project and create a pull request. A few tips:
 
+- Submit JavaScript changes to the [Chartkick.js](https://github.com/ankane/chartkick.js) repo.
 - Keep changes to a minimum. If you have multiple features or fixes, submit multiple pull requests.
 - Follow the existing style. The code should read like it’s written by a single person.
 
 Feel free to open an issue to get feedback on your idea before spending too much time on it.