Implement a basic REST alarm notification

This change adds schemes http:// to the alarm notifier.

The URL is called as a POST request.
The body of request contains a json dictionnary with alarm state and the
reason.

Change-Id: I0dbdd6afdef1a88602c9fbc55d651d3d8f6ad3e0
Blueprint: alarm-notifier
Merge "Implement a basic REST alarm notification"