Merge pull request #21 from cfs-energy/hassec-patch-1

Add DOI badge to README

README.md

@@ -5,5 +5,6 @@ cfspopcon: 0D Plasma Calculations & Plasma OPerating CONtours
 [![Checked with mypy](http://www.mypy-lang.org/static/mypy_badge.svg)](http://mypy-lang.org/)
 [![Documentation Status](https://readthedocs.org/projects/cfspopcon/badge/?version=latest)](https://cfspopcon.readthedocs.io/en/latest/?badge=latest)
 [![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/cfs-energy/cfspopcon/HEAD)
+[![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.10054880.svg)](https://doi.org/10.5281/zenodo.10054880)
 
 For more information please have a look at our [documentation](https://cfspopcon.readthedocs.io/en/latest/).