Tiny usage tip fix for action & mailer gen commands

buffalo/cmd/generate/action.go

@@ -15,7 +15,7 @@ var actionOptions = struct {
 
 //ActionCmd is the cmd that generates actions.
 var ActionCmd = &cobra.Command{
-	Use:     "action [name] [actionName...]",
+	Use:     "action [name] [handler name...]",
 	Aliases: []string{"a", "actions"},
 	Short:   "Generates new action(s)",
 	RunE: func(cmd *cobra.Command, args []string) error {

buffalo/cmd/generate/mailer.go

@@ -12,7 +12,7 @@ var mailer = mail.Generator{}
 
 // MailCmd for generating mailers
 var MailCmd = &cobra.Command{
-	Use:   "mailer",
+	Use:   "mailer [name]",
 	Short: "Generates a new mailer for Buffalo",
 	RunE: func(cmd *cobra.Command, args []string) error {
 		if len(args) == 0 {