Added supervisor-stdout so that all components stdout/stderr are directed to the Docker-monitored supervisor
process. This enables viewing stdout from either 'docker logs' or 'fig logs'.
Added a fluentd container responsible for collecting all stdout from all containers. It does not impose
any requirement on other containers but simply hack from Docker internal log collecting facility.

Currently fluentd just write to a local file, which should be refined to a log management system later.