CLOUDSTACK-2563: Network ACL: Allow protocol 1(icmp) paired with icmp type/code
CLOUDSTACK-2681: Suppress failed to apply port forwarding rule error when rollback
CLOUDSTACK-2682: Sleep 1 second before switch to BACKUP

To prevent backup.sh preempt master.sh when keepalived switch to MASTER then
back to BACKUP immediately.

Since it would take at least 3 seconds for BACKUP to switch to MASTER(vrrp
timeout), the fix won't cause chaos when keepalive try to switch to MASTER.