Adding a notification plugin

[gcrahay]

I've created a third-party plugin named fir_async to send notifications when an incident is created or updated.

These notifications are sent via email and/or XMPP, but new methods can be easily added.

I am planning to add more events:

• Artifact added
• Artifact detached
• Incident status changed
• Incident commented
• ...

The core fir_abuse plugin added the Celery dependency in FIR, so I suggest adding this notification plugin as a core plugin into FIR as fir_notifications.

Would you like me to submit a PR?

[benjimons]

+1 to this. I was looking to make something similar, it would be nice to have both "events" and "incidents" individually configurable for notifications.

[gaelmuller]

We are always interested in pull requests, especially when they are in a separate plugin that people can chose to install or not.