Support for importing Alibaba Cloud MFA backup files

[zdm51]

阿里云的MFA可以先在阿里云APP上进行绑定，绑定之后可以在阿里云APP中选择备份MFA，从而导出一个MFA的备份文件（这个备份文件是一个文本文档），希望Aegis能够导入从阿里云APP导出的MFA备份文件进行使用，谢谢！

[alexbakker]

Please use English when filing an issue (using Google Translate is fine)

Before I create an Alibaba Cloud account to see what's going on there: Do you know what underlying OTP algorithm they're using? Is it TOTP? And does that export then simply contain the secret for TOTP?