Consider Adding A Citation File

[O957]

This repository (or some future version of it) is (I believe) under review for publication. To faciliate its citability, a CITATION cff file seems reasonable to employ:

• https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-citation-files
• https://citation-file-format.github.io/