chore(cli): better usage text

main.go

@@ -19,7 +19,6 @@ import (
 
 const (
 	name = "changeloguru"
-	description = "generate changelog from conventional commits"
 
 	currentDir       = "."
 	markdownFiletype = "md"
@@ -48,7 +47,7 @@ func main() {
 
 	app := &cli.App{
 		Name:  name,
-		Description: description,
+		Usage: "generate changelog from conventional commits",
 		Flags: []cli.Flag{
 			&cli.StringFlag{
 				Name:  fromFlag,
@@ -56,7 +55,7 @@ func main() {
 			},
 			&cli.StringFlag{
 				Name:  toFlag,
-				Usage: "generate to `COMMIT` (include that commit)",
+				Usage: "generate to `COMMIT`",
 			},
 			&cli.StringFlag{
 				Name:        versionFlag,