报错内容：
App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.
权宜之计：
1、在Info.plist中添加 NSAppTransportSecurity 类型 Dictionary ;
2、在 NSAppTransportSecurity 下添加 NSAllowsArbitraryLoads 类型Boolean ,值设为 YES;
