[Governance] set up repository to archive to zenodo on release

[cthoyt]

Submission of the molecular inorganics software article to J Chem Inf will require referencing a Zenodo archive.

We should set up this repository to automatically archive to Zenodo on each release, following https://help.zenodo.org/docs/github/enable-repository/.

More information also available at https://github.com/OpenScienceMOOC/Module-5-Open-Research-Software-and-Open-Source/blob/master/content_development/Task_2.md