Notification using Slack API

[cblancoz]

Hello,

I have a couple of devices with the service watch notifications enabled and configured with Slack but when the notification is received in the channel I can't identify which is which, how I can change the default name of the devices, for all devices are showing as "Netgate pfSense Plus", all notification config are using the global variable g$, it should great if we can take the name of hostname especially when you have more that one instance configured

Thanks