This way we are able to edit notification behavior per notifier.
This would be usefull to let some notifiers send notifications,
even when the state doesn't change, or with custom condition.
Signed-off-by: Thibault Chataigner <t.chataigner@criteo.com>
If the message field is left empty for Pushover notifications, the API will return an error. This adds a default message if the message would otherwise be empty.
This fixes#8006.
