docker-ce_清华源
https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/fedora/
fedora25 docker-ce版本:
https://docs.docker.com/install/linux/docker-ce/fedora/#install-docker-ce
dnf -y install dnf-plugins-core
dnf config-manager \
--add-repo \
https://download.docker.com/linux/fedora/docker-ce.repo