There are two reasons for this change:
1. Past migrations depending on models will not work once a model is
removed, and they won't work if we remove Globalize either
2. We were getting a conflict in the schema file; when run under Rails
5.0, these migrations were generating a different schema than in Rails
5.1, due to the way the `create_translation_table!` method handles the
`id: :serial` attribute.
DEPRECATION WARNING: Directly inheriting from ActiveRecord::Migration
is deprecated. Please specify the Rails release the migration was
written for:
class MigrationClass < ActiveRecord::Migration[4.2]
(called from require at bin/rails:4)
