Adds bandit configuration template and exclude some of
tests that we don't want to fix for the moment.
Keeping job unvoted so that we can keep an eye on possible
issues while not breaking gate.
The old generate_sample.sh is broken already as it refers to
non-existing openstack/common path.
Let's use oslo-config-generator as many other OpenStack projects do.
Also, where applicable, option descriptions are updated with the
corresponding kernel parameters to set those options durig pxe boot.
Updated file tox.ini allows to check code style in all ".sh" files
included in Ironic Python Agent. Checking can be invoked by calling either
"tox" or "tox -e pep8".