add flock and timeout protection for fire-ping.sh in brotab
add flock and timeout protection for fire-ping.sh in brotab

MelvinTo/firewalla,firewalla/firewalla,firewalla/firewalla,MelvinTo/firewalla,MelvinTo/firewalla,firewalla/firewalla,firewalla/firewalla,MelvinTo/firewalla,MelvinTo/firewalla,firewalla/firewalla