Add CITATION.cff

[schackartk]

Current problem

I would like to cite pylint in a research article and it is unclear how pylint should be cited.

Desired solution

I would like pylint to have a CITATION.cff file in the root of the repository.

GitHub recommends, and integrates support for, CITATION.cff files. Inclusion of this file would immediately have these benefits:

• Users will have the necessary metadata to properly cite pylint.
• GitHub can automatically generate both APA and BibTeX formatted citations. A "Cite this repository" option will automatically appear on the repo's sidebar when viewed on a desktop browser.
• Reference managers like Zotero will automatically detect the metadata so the user can save the citation to their library.

Additional context

Examples of popular packages using this are pandas and tensorflow.

I would be happy to create an initial version of this and open a PR if there is interest in possibly merging it after refinement.

[Pierre-Sassoulas]

Thank you for opening the issue and for citing pylint in your research. Definitely interested by merging what you can suggest and I think that would be pretty cool to have.