VOL-2168 - add the ability to specify default formats and ordering

Change-Id: Ie867bbd8d055e34f26eb43466a92f1d1954e35d4
diff --git a/cmd/voltctl/voltctl.go b/cmd/voltctl/voltctl.go
index caa0f40..5b70bac 100644
--- a/cmd/voltctl/voltctl.go
+++ b/cmd/voltctl/voltctl.go
@@ -42,11 +42,12 @@
 	if len(compval) > 0 {
 		os.Unsetenv("GO_FLAGS_COMPLETION")
 		pp := flags.NewNamedParser(path.Base(os.Args[0]), flags.Default|flags.PassAfterNonOption)
-		_, err := pp.AddGroup("Global Options", "", &commands.GlobalOptions)
-		if err != nil {
-			panic(err)
+		if _, err := pp.AddGroup("Global Options", "", &commands.GlobalOptions); err != nil {
+			commands.Error.Fatalf("Unable to set up global options for command completion: %s", err.Error())
 		}
-		pp.Parse()
+		if _, err := pp.Parse(); err != nil {
+			commands.Error.Fatalf("Unable to parse command line options for command completion: %s", err.Error())
+		}
 		os.Setenv("GO_FLAGS_COMPLETION", compval)
 	}