Update README.md w/ DOI shield

README.md

@@ -4,6 +4,8 @@ Sample data set exemplifying an idealized data processing pipeline:
 
 ![alt text](https://github.com/RISE-UNIBAS/rheinschifffahrt/blob/master/docs/pipeline.png?raw=true)
 
+[![DOI](https://zenodo.org/badge/465364947.svg)](https://zenodo.org/badge/latestdoi/465364947)
+
 ## Creator
 
 This dataset was created by the University of Basel's Research and Infrastructure Support RISE ([email protected]) in 2022. It is based on the digital collection "Basler Rheinschifffahrt-Aktiengesellschaft, insbesondere über die Veräusserung des Dieselmotorbootes 'Rheinfelden' und die Gewährung eines Darlehens zur Finanzierung der Erstellung des Dieselmotorbootes 'Rhyblitz' an diese Firma" (shelf mark: `CH SWA HS 191 V 10`, persistent link: http://dx.doi.org/10.7891/e-manuscripta-54917, referred to as "the collection" in what follows) of the Schweizer Wirtschaftsarchiv.