CONTRIBUTING.md in h3-3.4.4

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 # Contributing to the H3 project
 
 Pull requests and Github issues are welcome!
 
+Planned improvements and changes are listed on the [H3 Roadmap](https://github.com/uber/h3/wiki/Roadmap). Roadmap items are currently discussed in Github issues. Feel free to open a discussion about an existing roadmap item or proposing a new one.
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 ## Pull requests
 
 * Please include tests that show the bug is fixed or feature works as intended.
 * Please add a description of your change to the Unreleased section of the [changelog](./CHANGELOG.md).
 * Please open issues to discuss large features or changes which would break compatibility, before submitting pull requests.