Update help

Signed-off-by: jcsiadal <jeremy.c.siadal@intel.com>

internal/app/wwctl/overlay/show/root.go

@@ -6,10 +6,9 @@ import (
 
 var (
 	baseCmd = &cobra.Command{
-		Use:   "show [flags] (overlay kind) (overlay name) (overlay file)",
+		Use:   "show [OPTIONS] {system|runtime} OVERLAY_NAME FILE",
 		Short: "Show (cat) a file within a Warewulf Overlay",
-		Long: "This command will output the contents of a file within a given\n" +
-			"Warewulf overlay.",
+		Long: "This command displays the contents of FILE within OVERLAY_NAME.",
 		RunE:    CobraRunE,
 		Aliases: []string{"cat"},
 		Args:    cobra.ExactArgs(3),