This updates the scripts for deploying fluentd to include
overrides for enabling prometheus monitoring. Despite not
deploying prometheus in the osh-infra-logging job, we can still
leverage the post run job to gather metrics from the exporters
service. This gives us the means for verifying the functionality
of the exporter
Change-Id: Id98474de89d86419157635007e2f114f0947498e
7c093716ca