You're welcome to contribute to this project.
By default, we require contributors to accept this extra condition. It's cut from the Apache 2.0 license, but as this project is released with the MIT license, this is the license referred to:
Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of the License, without any additional terms or conditions. Notwithstanding the above, nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions.
We prefer that you open a Github issue before starting to work on a contribution. This allows us to comment and agree or disagree before any work is committed. Make sure to look through the existing issues to make sure it has not already been reported.
Once you have a patch you feel should be included in the main project, open a Pull Request. We will review it on a best effort basis.