docs(build): Add descriptions to grunt tasks that lack them.

Closes #608

grunttasks/l10n-create-json.js

@@ -16,7 +16,7 @@ module.exports = function (grunt) {
   'use strict';
 
   // po2json is configured in po2json.js
-  grunt.registerTask('l10n-create-json', function () {
+  grunt.registerTask('l10n-create-json', 'Create localized string bundles for the client.', function () {
     if (! fs.existsSync(jsonOutputPath)) {
       mkdirp.sync(jsonOutputPath);
     }

grunttasks/l10n-extract.js

@@ -15,7 +15,7 @@ const messagesOutputPath = path.join(__dirname, '..', 'locale', 'templates', 'LC
 module.exports = function (grunt) {
   'use strict';
 
-  grunt.registerTask('l10n-extract', function () {
+  grunt.registerTask('l10n-extract', 'Extract strings from templates for localization.', function () {
     var done = this.async();
 
     if (! fs.existsSync(messagesOutputPath)) {

grunttasks/l10n-fetch-strings.js

@@ -18,7 +18,7 @@ const localePath = path.join(__dirname, '..', 'locale');
 module.exports = function (grunt) {
   'use strict';
 
-  grunt.registerTask('l10n-fetch-strings', function () {
+  grunt.registerTask('l10n-fetch-strings', 'Fetch localized strings from the localization repo.', function () {
     var done = this.async();
 
     if (! fs.existsSync(localePath)) {

grunttasks/l10n-merge.js

@@ -9,7 +9,7 @@ const path = require('path');
 module.exports = function (grunt) {
   'use strict';
 
-  grunt.registerTask('l10n-merge', function () {
+  grunt.registerTask('l10n-merge', 'Merge extracted strings with .PO files.', function () {
     var done = this.async();
     grunt.util.spawn({
       cmd: path.resolve(__dirname, '..', 'scripts', 'merge_po.sh'),

grunttasks/selectconfig.js

@@ -15,7 +15,7 @@ module.exports = function (grunt) {
     dist: path.join(CONFIG_ROOT, 'production.json')
   };
 
-  grunt.registerTask('selectconfig', function(target) {
+  grunt.registerTask('selectconfig', 'Select configuration files for the running environment.', function(target) {
     if (! target) {
       target = 'app';
     }

grunttasks/server.js

@@ -5,7 +5,7 @@
 module.exports = function (grunt) {
   'use strict';
 
-  grunt.registerTask('server', function (target) {
+  grunt.registerTask('server', 'Start the server after performing necessary build.', function (target) {
     if (target === 'dist') {
       return grunt.task.run(['build', 'serverproc:dist']);
     }

grunttasks/serverproc.js

@@ -7,7 +7,7 @@ module.exports = function (grunt) {
 
   var runServer = require('../scripts/run_locally');
 
-  grunt.registerTask('serverproc', function () {
+  grunt.registerTask('serverproc', 'Start the server. ** Use `grunt server:<target>` instead **.', function () {
     runServer(this.async());
   });
 };