Updated Whisper Push Notifications (markdown)

Whisper-Push-Notifications.md

@@ -388,6 +388,9 @@ filter.watch(function (error, result) {
 ```
 We provide all the code for `Device B` in a single chunk. Basically, all that `Device B` does, is: wait for shared key, register device, trigger notification.
 
+### 4. Checking subscription status and unsubscribing
+
+
 # Complete Sample
 
 Full sample page used for testing can be found here: https://gist.github.com/farazdagi/5ac082ddf006d00de422385f07d41ad3