Only show transfer stats on commands which transfer stuff - fixes #849

cmd/purge/purge.go

@@ -21,7 +21,7 @@ you want to selectively delete files.
 	Run: func(command *cobra.Command, args []string) {
 		cmd.CheckArgs(1, 1, command, args)
 		fdst := cmd.NewFsDst(args)
-		cmd.Run(true, command, func() error {
+		cmd.Run(true, false, command, func() error {
 			return fs.Purge(fdst)
 		})
 	},