Fix race between event write and thread processing
Fix race between event write and thread processing

Journal rows are written in the pre-commit hook,
thus available only when the original operation (i.e. add port) commits.
In order to prevent race condition the journal triggering  was moved
from pre-commit to post-commit.

Change-Id: I0b52ccb43b405e7dd3d4f65066169a8bbee58c39
Closes-Bug: #1569986

openstack/networking-odl,openstack/networking-odl,openstack/networking-odl