Builds a fluentd Docker image based on alpine Linux for use in a Kubernetes environment.
All plugins and dependencies for fluentd are listed in the Gemfile and are directly installed in the image.
The image will run as a non-root user called fluent with uid 1000.
During startup, fluentd will search for additional configuration files in /etc/fluent/config.d/*.conf. Make sure to have a ConfigMap with your config mounted in this location.