[Bug 1166312] etcd unit should support command line options

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1166312

--- Comment #1 from Eric Paris  ---
etcd (at least 0.4) has a config file.  /etc/etcd/etcd.conf

Which is sourced and used by etcd itself.

This might go away in 0.5 or 0.6, in which case we will look to support the
model you describe.  But right now, I don't see a bug here.