Added networking section to Operational Excellence

Operational_Excellence.md

@@ -21,7 +21,7 @@ The severity or importance of each topic is indicated by an emoji in the topic n
 * :cloud: Medium
 * :partly_sunny: Low
 
-## Operational principles:
+## Operational principles
 
 * TBD
 
@@ -41,6 +41,8 @@ Table of Contents
   * AKS cluster
   * AKS master components
   * acs-engine
+* Networking
+  * Public and Private Ingresses
 * Identity and permissions
   * Azure RBAC roles
   * Kubernetes RBAC