Using hello call for occasional alerts

[mudar]

We could use the POST /v1/hello endpoint to send alerts to users who don't update their app. This would be used in cases where Notifications can't do the job... Some Examples:

• server is down for a couple of days
• old app version is no longer supported, please update
• new feature (snow removal) has been added. Update your app to get the feature

My suggestion would be something like

alert: {
  "title": "Update required",
  "body": "Your app version is no longer supported. Please update app",
  "force_close": true,
  "action": "maybe?",
  "url": "maybe?"
}

subscribing @antonino-u

[mudar]

A good example!