Make Rediscovered Template Settings Apply to Active Incidents

Without this, it is required to pick through what active incidents are affected by the change, remove the thresholds, and rediscover the devices. There is really no point in needing to do that and I can't think of an occasion where someone would want to keep the old settings for a current issue.

If we were to remove all thresholds and then rediscover everything, it could possibly take hours, meaning we could not be monitoring customer devices for that long.