Added custom usage statements to generator commands

Author: begedin

lib/cli/component.js

@@ -7,6 +7,7 @@ var ui = require('../ui');
 
 program
   .arguments('<addonName>')
+  .usage('<addonName')
   .action(function(addonName) {
     if (addonName) {
       require('../tasks/component')({ addonName: dasherize(addonName) }).catch(ui.error);

lib/cli/helper.js

@@ -7,6 +7,7 @@ var ui = require('../ui');
 
 program
   .arguments('<addonName>')
+  .usage('<addonName')
   .action(function(addonName) {
     if (addonName) {
       require('../tasks/helper')({ addonName: dasherize(addonName) }).catch(ui.error);

lib/cli/library.js

@@ -7,6 +7,7 @@ var ui = require('../ui');
 
 program
   .arguments('<addonName>')
+  .usage('<addonName')
   .action(function(addonName) {
     if (addonName) {
       require('../tasks/library')({ addonName: dasherize(addonName) }).catch(ui.error);