build: switch source archive to xz compression
Mention gerrit in the README
Change-Id: I468cedde1a15f760aef00ac2995dd5f73728b89e
diff --git a/docs/index.rst b/docs/index.rst
index 2f5689d..691707b 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -23,4 +23,5 @@
ChronoSync is free software: you can redistribute it and/or modify it under the terms
of the GNU General Public License as published by the Free Software Foundation, either
-version 3 of the License, or (at your option) any later version.
+version 3 of the License, or (at your option) any later version. See `COPYING.md
+<https://github.com/named-data/ChronoSync/blob/master/COPYING.md>`__ for details.