To ensure clear collaboration, all commits must be "Signed-off by." This signifies that the committer has the necessary rights to contribute this work under the same license and has agreed to adhere to the Developer Certificate of Origin (please refer to http://developercertificate.org/ for more details).
All contributors retain the original copyright to their stuff, but by contributing to this project, you grant a world-wide, royalty-free, perpetual, irrevocable, non-exclusive, transferable license to all users under the terms of the license under which this project is distributed.
(If you are new to GitHub, you might start with a basic tutorial and check out a more detailed guide to pull requests.)