add screenshot and toc node

Author: mamccrea

articles/stream-analytics/TOC.yml

@@ -120,6 +120,8 @@
       href: blob-output-managed-identity.md
     - name: Authenticate with managed identity - Power BI
       href: powerbi-output-managed-identity.md
+    - name: Encrypt your data
+      href: data-protection.md
   - name: Build solutions
     items:
     - name: Twitter sentiment analysis

articles/stream-analytics/data-protection.md

@@ -39,6 +39,8 @@ Use the following steps to configure your storage account for private data asset
 
 1. Select a storage account from your subscription. Note that this setting cannot be modified throughout the life cycle of the job. 
 
+   ![Private data storage account settings](./media/data-protection/storage-account-create.png)
+
 ## Private data assets that are stored
 
 Any private data that is required to be persisted by Stream Analytics is stored in your storage account. Examples of private data assets include: