add image user to inspect data

Signed-off-by: baude <bbaude@redhat.com>

Closes: #1036
Approved by: rhatdan

libpod/image/image.go

@@ -815,6 +815,7 @@ func (i *Image) Inspect(ctx context.Context) (*inspect.ImageData, error) {
 		},
 		GraphDriver:  driver,
 		ManifestType: manifestType,
+		User:         ociv1Img.Config.User,
 	}
 	return data, nil
 }