A simple WebThings Gateway notifier for sending push notifications via Pushover.
Log in to Pushover, add a new app, then copy the token.
On your gateway, navigate to Settings -> Add-ons. Next, click the plus (+) button and scroll down to install the Pushover Notifier.
With the notifier installed, click "Configure", then input the token you just created and your user key.
Now, you can go create some rules and use Pushover as a notification output.