add watchfile task and jasmine task,but not tested!

Gruntfile.js

@@ -1,5 +1,7 @@
 //npm install -g grunt-cli
 //npm install --save-dev grunt-shell
+//npm install --save-dev grunt-contrib-watch
+//npm install --save-dev grunt-contrib-jasmine
 //Usage: grunt shell
 module.exports = function (grunt) {
     grunt.initConfig({
@@ -9,9 +11,32 @@ module.exports = function (grunt) {
                 command: 'phantomjs system_api.js jacky.yao'
             }
         },
+        //configure jasmine task
+        //https://github.com/gruntjs/grunt-contrib-jasmine
+        jasmine: {
+            pivotal: {
+                sec: 'js/src/**/*.js',
+                optins: {
+                    specs: 'js/spec/*Spec.js'
+                }
+            }
+        },
+        // configure file watcher
+        // https://github.com/gruntjs/grunt-contrib-watch
+        watch: {
+            scripts: {
+                files: [ 'js/src/**/*.js' ],
+                tasks: [ 'jasmine' ],
+                options: {
+                    spawon: false,
+                }
+            }
+        }
         //set up tasks
     });
     grunt.loadNpmTasks('grunt-shell');
+    grunt.loadNpmTasks('grunt-contrib-watch');
+    grunt.loadNpmTasks('grunt-contrib-jasmine');
     grunt.registerTask('default',['shell:phantomjs']);
 
 };