Merge pull request #154 from dotcloud/153-commitnorepo

Clearer information when listing images
diff --git a/commands.go b/commands.go
index 96d38a9..869581c 100644
--- a/commands.go
+++ b/commands.go
@@ -559,8 +559,8 @@
 		for id, image := range allImages {
 			if !*quiet {
 				for idx, field := range []string{
-					/* REPOSITORY */ "",
-					/* TAG */ "",
+					/* REPOSITORY */ "<none>",
+					/* TAG */ "<none>",
 					/* ID */ id,
 					/* CREATED */ HumanDuration(time.Now().Sub(image.Created)) + " ago",
 					/* PARENT */ srv.runtime.repositories.ImageName(image.Parent),