This introduces a mechanism for generating the logging.conf
file for the openstack services via the values. This allows us to
define loggers, handlers, and formatters for the services and the
modules they're composed of.
This also allows us to take advantage of the oslo fluent handler
and formatter. The fluent handler and formatter give us the
following benefits: sending logs directly to fluentd instead of
routed to stdout/stderr and then through fluentbit to fluentd,
project specific tags on the logged events (enables us to define
more robust filters in fluentd for aggregation if required),
full traceback support, and additional metadata (modules that
created logged event, etc)
Depends-On: https://review.openstack.org/577796
Change-Id: I63340ce6b03191d93a74d9ac6947f0b49b8a1a39