[$] Managing expectations with a contributions and credit policy

Maintainers of open-source projects sometimes have disagreements withcontributors over how contributions are reviewed, modified, merged, andcredited. A written policy describing how contributions are handled canhelp maintainers set reasonable expectations for potential contributors.In turn, that can make the maintainer's job easier because it can helpreduce a source of friction in the project. A guide to help create thiskind of policy for a project has recently been developed.