UI Updates with a few minor fixups scattered here and there

internal/app/wwctl/container/build/main.go

@@ -18,6 +18,11 @@ func CobraRunE(cmd *cobra.Command, args []string) error {
 		containers = args
 	}
 
+	if len(containers) == 0 {
+		fmt.Println(cmd.Help())
+		os.Exit(0)
+	}
+
 	for _, c := range containers {
 		if container.ValidSource(c) == false {
 			wwlog.Printf(wwlog.ERROR, "VNFS name does not exist: %s\n", c)

internal/app/wwctl/container/build/root.go

@@ -4,11 +4,11 @@ import "github.com/spf13/cobra"
 
 var (
 	baseCmd = &cobra.Command{
-		Use:   "build (container location | node search pattern)",
-		Short: "VNFS Image Build",
-		Long:  "VNFS kernel images",
+		Use:   "build [flags] [container name]...",
+		Short: "(Re)build a bootable VNFS image",
+		Long:  "This command will build a bootable VNFS image from an imported container image.",
 		RunE:  CobraRunE,
-		Args:  cobra.RangeArgs(0, 1),
+		Args:  cobra.MinimumNArgs(1),
 	}
 	BuildForce bool
 	BuildAll   bool