Update Readme with screenshot

Author: dlamspl

README.md

@@ -7,7 +7,7 @@ Splunk attack range repo can be found [here](https://github.com/splunk/attack_ra
 ## What is it ?
 It is a Splunk app that provides dashboards that enable a user of Splunk attack range to have better view of what simulations run, relevant security content from other Splunk apps and overview of the available Atomic Red tests.
 
-## Compatibility
+## Compatibility and dependencies
 v1.0.0 of the app is compatible with the below
 
 + Splunk 8.0.x
@@ -22,3 +22,8 @@ v1.0.0 of the app has the following depencencies
 + [Security essentials v3.1.x](https://splunkbase.splunk.com/app/3435/)
 + [Status Indicator - Custom Visualization](https://splunkbase.splunk.com/app/3119/)
 
+## What does it look like ?
+
+Main dashboard is showing simulations run, users, hosts, MITRE ATT&CK tactics and techniques, tests executed and potential mapping with analytic stories. 
+
+![Main Dashboard](appserver/static/docs/img/ar_main_dashboardv1.0.png?raw=true "Main Dashboard")