New docker Statistics Collector

[jhunt]

I would like to see a new collector for Docker, that connects to the docker socket (usually this will be bind-mounted into the container from the host) and collects information about all of the containers that are running.

Here's some example requests:

curl http://localhost:9098/containers/json | jq -r . | less
curl http://localhost:9098/containers/$CONTAINER/stats?stream=false | jq -r . | less

See https://docs.docker.com/engine/api/#31-containers for more details on the API.