[ifmap-server] Update {owner,group}ship for ifmap config

Mentioned by Edouard, the publisher.properties config must be writeable
by the irond user (contrail).

Change-Id: I618d2b403a4e7dce2034216128e2e16a6e111c35
(cherry picked from commit 477c157a320985fbef0a869e901d0e79ab01a1b2)
Merge "[ifmap-server] Update {owner,group}ship for ifmap config" into R1.06