Check that all po/pot files are valid
Check that all po/pot files are valid

Perform minimal checks on po and pot files so that no broken files can
get imported.

Change-Id: I328fc11c688c16737ae88984e4778483ce5db5ab
Co-Authored-By: Clark Boylan <635fc31d01fa593720982fa0568e87170cedbe2c@gmail.com>
Related-Bug: #1298645

openstack/ironic-lib,citrix-openstack-build/ironic-lib,faizan-barmawer/elytics,NaohiroTamura/ironic-lib,faizan-barmawer/ironic-lib