http://www.saitjr.com/ios/ios-export-remote-notification-p12-pem-file.html iOS导出远程推送所需要的P12 或pem文件
http://www.brighttj.com/ios/ios-debugging.html iOS真机调试证书
https://www.jianshu.com/p/fb180965ff76
https://www.jianshu.com/p/cc952ea07a08