Replace usage of gettextutils with oslo.i8ln

From https://github.com/openstack/neutron/commit/3f44c9e27874511f05e2338c10e836361776ed88
and https://github.com/openstack/neutron/commit/dac6a0c79e56a8b724dcfbf2c3058fbbc79cc7b0

RM10742
Merge pull request #286 from jmeridth/fix_upstream_changes

Fix upstream neutron changes, items removed from neutron.common