Fix dead link to license

README.rst

@@ -112,7 +112,7 @@ Links
 * `Issue Tracker <https://github.com/borgbackup/borg/issues>`_
 * `Bounties & Fundraisers <https://www.bountysource.com/teams/borgbackup>`_
 * `Mailing List <https://mail.python.org/mailman/listinfo/borgbackup>`_
-* `License <https://borgbackup.github.io/borgbackup/authors.html#license>`_
+* `License <http://borgbackup.readthedocs.org/en/stable/authors.html#license>`_
 
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