This patch removes get_cfg_opts from the plugin class,
and moves all configuration directly into designate.conf.
There are no changes in the generated configuration due
to this patch.
Finally, this complets the blueprint to centralize all
configuration, and is a follow up to this patch
I3be68bf294157631a9bac128df0841220020de96
blueprint centralize-config-designate
Change-Id: I007fc004fc533950c5eda3974f41f05c6db5b43f
097ffec548