Filter out unnecessary garbage tags from the "hello-world" description

hello-world/README.md

@@ -27,7 +27,6 @@ For more information about this image and its history, please see the [relevant
 	
 	$ docker images hello-world
 	REPOSITORY   TAG     IMAGE ID      VIRTUAL SIZE
-	hello-world  build   b448da95d884  130.4 MB
 	hello-world  latest  91c95931e552  910 B
 
 ![logo](https://raw.githubusercontent.com/docker-library/docs/master/hello-world/logo.png)

hello-world/update.sh

@@ -13,7 +13,7 @@ echo
 	docker run --rm hello-world
 	echo
 	echo '$ docker images hello-world'
-	docker images hello-world | awk -F'  +' '{ print $1"\t"$2"\t"$3"\t"$5 }' | column -t -s$'\t'
+	docker images hello-world | awk -F'  +' '$2 == "TAG" || $2 == "latest" { print $1"\t"$2"\t"$3"\t"$5 }' | column -t -s$'\t'
 } | sed 's/^/\t/'
 
 echo