今天在调用SDWebImage的时候发现Xcode会报错：
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.
xcode会将HTTP格式的阻断
解决方法：
在info.plist文件中添加：
App Transport Security Settings (是个Dictionary)
并在其中添加Allow Arbitrary Loads，设置为YES
解决。
