This PS moves alertmanager to use the endpoints section and
lookups to set the ports it serves on.
Change-Id: I62108ca207f615d10d0b4385da204214b9aeae32
This adds the prometheus- prefix to the alertmanager,
kube-state-metrics and node exporter charts to reflect their
intended usage as part of a prometheus centric monitoring solution
This will imply a logical grouping of these components, similar to
their deployment in the osh-infra gates
Change-Id: I4f391a10b64389022f01a94ea3704c110f8f9bb5