Nothing is being translated in placement so, for the sake of being clean
and tidy, this patch removes the framework for translation and the
import of oslo.i18n.
Originally the hope was we could remove the dependency on oslo.i18n and
Babel entirely to save some disk space but many other oslo-related libs
depend on oslo.i18n so they are present anyway. [1]
[1] http://lists.openstack.org/pipermail/openstack-discuss/2019-March/004220.html
Change-Id: Ia965d028b6f7c9f04d1f29beb12f4862585631d5