Add a script to extract the ironic_tempest_plugin/ directory from the
openstack/ironic repository. Then cherry-pick all of those commits
into this repository.
Also make ironic_tempest_plugins/__init__.py an empty file so 'diff'
will be correct.
Remove the following files, so 'diff' will be correct:
ironic_tempest_plugin/tests/base.py
ironic_tempest_plugin/tests/test_ironic_tempest_plugin.py
Ignore E129 errors in flake8, like we do in Ironic. As it will fail
pep8 when we import all the upcoming patches.
Change-Id: I1625128717c8a848c6d673314b09d0a6c9c96679