Update README with copyright year

Author: jplanasc

README.md

@@ -114,4 +114,5 @@ Follow the next guidelines when making a contribution:
 The development of this software was supported by funding to the Blue Brain Project,
 a research center of the École polytechnique fédérale de Lausanne (EPFL), from the
 Swiss government’s ETH Board of the Swiss Federal Institutes of Technology.
- 
+
+Copyright (c) 2021 Blue Brain Project/EPFL