docs: Move mailing list up

Readme.md

@@ -67,6 +67,14 @@ together with past releases until 4.0. When choosing a release, we recommend tha
 you get the latest bugfix release in that line. For example, for 4.1 you would like
 to use 4.1.2.
 
+### Join the community
+
+Please consider subscribing to our
+[mailing list](http://espressomd.org/wordpress/community-and-support/mailing-lists/)
+if you're actively using ESPResSo, as we occasionally need community
+feedback when making decisions on the future of specific features in
+upcoming releases. You'll also get notifications on bugfix releases.
+
 ### Please cite us!
 
 If you use ESPResSo to publish scientific results, we would ask you to
@@ -77,14 +85,6 @@ The authors of these contributions kindly ask you to cite the relevant
 publications, as indicated in the documentation. For detailed instructions, see
 [How to cite ESPResSo](http://espressomd.org/html/doc/introduction.html#how-to-cite-espresso).
 
-### Join the community
-
-Please consider subscribing to our
-[mailing list](http://espressomd.org/wordpress/community-and-support/mailing-lists/)
-if you're actively using ESPResSo, as we occasionally need community
-feedback when making decisions on the future of specific features in
-upcoming releases. You'll also get notifications on bugfix releases.
-
 ## License
 
 Copyright (C) 2010-2019 The ESPResSo project