Enable multiworker setup of contrail-api

PROD-18175

Change-Id: I7188b775c004b3354d032de70eccbce11742b6ba
diff --git a/README.rst b/README.rst
index b308fe2..825b1c0 100644
--- a/README.rst
+++ b/README.rst
@@ -880,6 +880,17 @@
           pci: 0000:81:00.1
       ...
 
+Increase number of contrail-api workers
+---------------------------------------
+
+.. code-block:: yaml
+
+    opencontrail:
+      ...
+      config:
+        api_workers: 3
+      ...
+
 Increase number of alarm-gen workers
 ------------------------------------