Making max_allowed_address_pair configurable option

Option can now be managed by salt for neutron server, gateway, or
compute node

Change-Id: I7ef8a9b036d15fd5a8ea36141a4822156198f470
Related-Prod: PROD-28532
diff --git a/README.rst b/README.rst
index c682b23..657ca3e 100644
--- a/README.rst
+++ b/README.rst
@@ -1469,6 +1469,24 @@
           rbac:
             enabled: True
 
+Increase maximum number of allowed address pairs per instance
+-----------------------------------
+
+Neutron Server:
+
+.. code-block:: yaml
+
+    neutron:
+      server:
+        max_allowed_address_pair: 20
+
+Neutron generic node (compute or gateway):
+
+.. code-block:: yaml
+
+    neutron:
+      max_allowed_address_pair: 20
+
 Enhanced logging with logging.conf
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