add support for etcd over ssl

Change-Id: If777a3835d6f8cdd0e4565d149cc2070580dcd9c
diff --git a/README.rst b/README.rst
index 0fa35e4..cf05053 100644
--- a/README.rst
+++ b/README.rst
@@ -8,6 +8,26 @@
 Sample pillars
 ==============
 
+Certificates
+-------------
+
+Use certificate authentication (for peers and clients). Certificates must be prepared in advance.
+
+.. code-block:: yaml
+
+    etcd:
+      server:
+        enabled: true
+        ssl:
+          enabled: true
+        bind:
+          host: 10.0.175.101
+        token: $(uuidgen)
+        members:
+        - host: 10.0.175.101
+          name: etcd01
+          port: 4001
+
 Single etcd service
 ---------------------