This adds the parameter pkcs11_provider, which can be set to the name of
or path to a PKCS#11 library (e.g. libpkcs11.so). ssh-keygen will then
use this library to have the token make any required signatures.
If this is used, signing_key needs to be set to a file containing the
public key that matches the private key on the token.
* Get rid of ansible.netcommon requirement by integrating module_utils/compat/ipaddress.py.
* Reorder imports.
* Update ignore.txt for plugins/module_utils/compat/ipaddress.py.
* Linting (flake8 / pep8).
* Remove accidentally commited test for ansible/ansible#66920.
