有了Docker自然想用Docker Compose，结果不小心掉坑里了，悲。。。
傻傻的直接curl是不行的，谁让我的是Raspberry呢
sudo curl -L "https://github.com/docker/compose/releases/download/1.25.4/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
好在官网提供了Alternative Install Options，里面列举了pip和docker两种替代方式，给了Alpine里的pip依赖。
For alpine, the following dependency packages are needed: py-pip, python-dev, libffi-dev, openssl-dev, gcc, libc-dev, and make.
自然是要用Python3的，先安装依赖包
sudo apt-get python3-pip python3-setuptools python3-dev build-essential libffi-dev wheel libssl-dev
pip3 install docker-compose
把/home/osmc/.local/bin/加入shell PATH，搞定
docker-compose --version
docker-compose version 1.25.4, build unknown
