Support docker and swarm

Get started

curl -LkO https://github.com/zhongl/passport/raw/master/docker-compose.yml 
curl -LkO https://github.com/zhongl/passport/raw/master/app.conf
DOMAIN=foo.bar docker-compose up -d
curl -k -v https://localhost -H 'Host: www.foo.bar' -H 'Cookie: jwt=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJwYXNzcG9ydCIsIm5hbWUiOiJ6aG9uZ2wiLCJleHAiOjE4NjYxNzI3MjV9.FomLr4SgRvHuI6iUnVZc2-Q9YQbNrh4eDWGbM09xoC8'