Use git-update-ref to delete a tag instead of rm()ing the ref file.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-tag.sh

@@ -47,8 +47,10 @@ do
     -d)
     	shift
 	tag_name="$1"
-	rm "$GIT_DIR/refs/tags/$tag_name" && \
-	        echo "Deleted tag $tag_name."
+	tag=$(git-show-ref --verify --hash -- "refs/tags/$tag_name") ||
+		die "Seriously, what tag are you talking about?"
+	git-update-ref -m 'tag: delete' -d "refs/tags/$tag_name" "$tag" &&
+		echo "Deleted tag $tag_name."
 	exit $?
 	;;
     -*)