Add notifier-config-syncer
Add notifier-config-syncer

Problem:
When notifiers are updated, configurations of alert-manager are not
synced.

Solution:
Sync configs on notifier updates

cjellick/rancher,rancherio/rancher,rancherio/rancher,rancher/rancher,cjellick/rancher,rancher/rancher,rancher/rancher,rancher/rancher,cjellick/rancher