DOC: Changed radART to medPhoton in RTK consortium

Same as RTKConsortium/RTK@5daf3f5

Author: Simon Rit

LICENSE

@@ -187,15 +187,15 @@
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright [2010-] [RTK Consortium]
+   Copyright [2010-2012] [RTK Consortium]
 
    The RTK consortium comprises:
      - CREATIS CNRS laboratory             https://www.creatis.insa-lyon.fr/
      - Massachusetts General Hospital      https://www.mgh.harvard.edu/
      - Université Catholique de Louvain    https://www.uclouvain.be/
      - IBA                                 https://www.iba-protontherapy.com/
      - Kitware                             https://www.kitware.com/
-     - radART                              http://www.open-radart.org/
+     - medPhoton                           https://www.medphoton.at/
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.