adding simple test for BindPFlag
adding simple test for BindPFlag

sankark/viper,ishidawataru/viper,mguindin/viper,jrossi/viper,streamrail/viper,samt42/viper,spf13/viper,mirrr/viper,istio/viper,henrylee2cn/viper,DLag/viper,vasu1124/viper,jacobstr/confer,zj8487/viper,akutz/viper,niccaluim/viper,dvln/viper