Create rel5.1.1.rst

R1/source/releases/rel5.1.1.rst

+Varnish 5.1.1
+=============
+
+ - 2017-03-16 /rubén
+
+`Source package can be found here <http://repo.varnish-cache.org/source/varnish-5.1.1.tar.gz>`_
+
+More information:
+
+* `List of changes and other good reasons to update to 5.1 </docs/trunk/whats-new/changes-5.1.html>`_
+* `Upgrading </docs/5.1/whats-new/upgrading-5.1.html>`_
+
+Operating System Specific Installation Guides
+---------------------------------------------
+
+* :ref:`install_ubuntu`
+* :ref:`install_debian`
+* :ref:`install_redhat`
+* :ref:`install_freebsd`
+
+EL7, Debian-Jessie, Ubuntu-Trusty and Ubuntu-Xenial packages can be found
+on `PackageCloud.io <https://packagecloud.io/varnishcache/varnish5>`_
+
+And yes, it is called 5.1.1 and we're one day late and it's all PHK's
+fault. He will tell us about it later, but first he'll do some
+housekeeping.