Revert "Replace usage of gettextutils with oslo.i8ln"

This reverts commit 8e4c9e93037a67ea32ff9dbd9626cff9e6b31e76.

We aren't ready for upstream changes yet.  Once we choose a new branch, we can add this back in so the tests pass.

Thinking out loud though, I think we will have an issue here since we are still pulling in master version of neutron as a requirement.

RM10742