Merge pull request #41 from Manabu-GT/ms-issue-26-27

Update README to add an instruction of showing/hiding an overlay via a notification

Author: Manabu-GT

README.md

@@ -117,6 +117,12 @@ Default is `true`.
 You can optionally supply string which must be your *activity's class name*.
 It will be used to create PendingIntent to start the activity when the notification is tapped.
 
+### Showing/Hiding an Overlay
+
+<img src="art/overlay_control_notification.png" width="50%" alt="DebugOverlay Control Notification">
+
+You can show/hide a debug overlay by tapping `Show/Hide` button on the notification shown.
+
 Provided Modules
 ------