Add support for HSTS header

Issue: PROD-20656

Change-Id: Iffdfb32e155dc38f17e8c4f2d46641e025ea66f2
diff --git a/README.rst b/README.rst
index a920e2d..0ac937d 100644
--- a/README.rst
+++ b/README.rst
@@ -452,6 +452,11 @@
               verify_depth: 1
               session_cache: 'shared:SSL:15m'
               session_timeout: '15m'
+              strict_transport_security:
+                max_age: 16000000
+                include_subdomains: False
+                always: true
+                enabled: true
 
 Nginx stats server (required by collectd nginx plugin)