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.
Change-Id: Id4a0df30ea573d52f3b359f357fe8f4a29751939
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".
Change-Id: Ie76605737c7db10a064f2aebfda388372a4c0591
Closes-Bug: #1625215