Use kolla_config to merge etcd's cert and key files into containers,
and set the ownership so the corresponding service can read the files.
Previously, etcd's cert and key files were directly bind mounted
in the etcd and cinder containers that need the files. An ACL was
added to ensure the corresponding services had read access to the
files on the host, which are owned by root. The ACL was cumbersome,
and required hardcoding the UID of each service.
Change-Id: Ic606e751cb046c34d33a94a2acd4313f4043441f
Depends-On: I0ea26253355a57b3721bfa6ceef3972eaabc5b1d
7bcdd2448b