Add zenodo badge to README.md (NeuralEnsemble#445)

* Update README.md

added zenodo batch with DOI

* Update README.md

Co-authored-by: Michael Denker <m.denker@fz-juelich.de>

Co-authored-by: Michael Denker <m.denker@fz-juelich.de>

README.md

@@ -6,6 +6,8 @@
 [![![PyPi]](https://img.shields.io/pypi/v/elephant)](https://pypi.org/project/elephant/)
 [![Statistics](https://img.shields.io/pypi/dm/elephant)](https://seladb.github.io/StarTrack-js/#/preload?r=neuralensemble,elephant)
 [![Gitter](https://badges.gitter.im/python-elephant/community.svg)](https://gitter.im/python-elephant/community?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
+[![DOI Latest Release](https://zenodo.org/badge/10311278.svg)](https://zenodo.org/badge/latestdoi/10311278)
+
 
 *Elephant* package analyses all sorts of neurophysiological data:
 spike trains, LFP, analog signals. The input-output data format is either