* mirrors: add mirror.leitecastro.com
* mirrors: mirrors.aliyun.com: fix x11 repo link
* mirrors: mirrors.cqupt.edu.cn,mirrors.ustc.edu.cn: reducing redirects
* mirrors: mirrors.dgut.edu.cn,mirrors.hit.edu.cn,mirrors.njupt.edu.cn,mirrors.scau.edu.cn:
removed as unavailable