This change allows a user to forward control plane logs
directly to Elasticsearch from Fluentd, rather than via
the Monasca Log API when Monasca is enabled. The Monasca
Log API can continue to handle tenant logs.
For many use cases this is simpler, reduces resource
consumption and helps to decouple control plane logging
services from tenant logging services.
It may not always be desired, so is optional and off by
default.
Change-Id: I195e8e4b73ca8f573737355908eb30a3ef13b0d6
ca1a80ab2f