错误描述：Error: [ng:areq] http://errors.angularjs.org/1.4.8/ng/areq?p0=HelloCtrl&p1=not%20a%20function%2C%20got%20undefined
at Error (native)
at http://localhost:8080/web/rs/angular.min.js:1:503
at qb (http://localhost:8080/web/rs/angular.min.js:1:8403)
at Qa (http://localhost:8080/web/rs/angular.min.js:1:8490)
at http://localhost:8080/web/rs/angular.min.js:1:38051
at w (http://localhost:8080/web/rs/angular.min.js:1:27806)
at D (http://localhost:8080/web/rs/angular.min.js:1:28162)
at g (http://localhost:8080/web/rs/angular.min.js:1:25189)
at g (http://localhost:8080/web/rs/angular.min.js:1:25206)
at http://localhost:8080/web/rs/angular.min.js:1:24829
Angular出现这种错误的原因，是由于没有在页面中使用模块引入controller导致的，修改内容如下：
添加：ng-app='app',然后在js中添加如下代码：
