Salt specification for adding fluentd to each node.

This pull request includes changes to the Salt setup to add a fluentd instance to each node. This fluentd instance will try to send the logs it has gather from the local Dockerfiles to port 9200 of the enclosing machine (e.g. a GCE VM). The assumption is at some point an instance of Elasticsearch at port 9200 will be available (e.g. by running a Kubernetes service).