Add possibility to specify osapi_volume_base_URL and public_endpoint

Running Cinder application without SSL under load balancer with SSL, we should
set osapi_volume_base_URL and public_endpoint with proper endpoints for the clients.
diff --git a/README.rst b/README.rst
index e2da026..7d6c011 100644
--- a/README.rst
+++ b/README.rst
@@ -135,6 +135,8 @@
 
 Cinder setup with zeroing deleted volumes
 
+.. code-block:: yaml
+
     cinder:
       controller:
         enabled: true
@@ -421,6 +423,17 @@
         default_availability_zone: my-default-zone
         storage_availability_zone: my-custom-zone-name
 
+public_endpoint and osapi_volume_base_url parameters:
+"public_endpoint" is used for configuring versions endpoint,
+"osapi_volume_base_URL" is used to present Cinder URL to users.
+They are useful when running Cinder under load balancer in SSL.
+
+.. code-block:: yaml
+
+    cinder:
+      controller:
+        public_endpoint_address: https://${_param:cluster_domain}:8776
+
 The default availability zone is used when a volume has been created, without specifying a zone in the create request. (this zone must exist in your configuration obviously)
 The storage availability zone is the actual zone where the node belongs to. Make sure to specify this per node.
 Check the documentation of OpenStack for more information