We still need to support Python 2.

Fixed usage of `else` right after return, or disable pylint
evaluation when it would play against code readability.

This is a style decision for ansible-freeipa, and in use by most
modules.

This is expected for most modules `main()` function.

All instances related to `ansible.module_utils.ansible_freeipa_module`,
which works. Future occurrences, if they happen, will likely not to be
a problem.

In some places, disabling the warnings rather than fixing it required
less changes, without compromising readability.

Protected access is required for AnsibleModule.

Although both warnings are relevant, the code style choosen for
ansible-freeipa currently require them to be disable.

This should be enabled in the future, but currently, nearly all
modules rely on `Exception`, and the changes would be too invasive.

Although it is an interesting setup, it currently has too many false
positives, disable comments are not working for duplicate-code, and
there are some expected duplications in the modules.

Fix usage of ipalib errors.

Various spelling/style fixes in README.md

Enhance ipaservice tests.

ansible_freeipa_module.py: Add ignore argument to compare_args_ipa

Hbacrule only make required member changes

The new argument ignore has been added to compare_args_ipa to ignore
attributes while comparing attributes of the user args and the object
args returned from IPA find or show command.

This code is using changes from
- Wolskie in PR #392
- jake2184 in PR #486

Currently user, group, host, hostgoup, hbacsvc and hbacsvcgroup members
are always added and removed with hbacrule_add_.. and hbacrule_remove_..
if they are given as parameters with action: member.

Now the module is using the new functions gen_intersection_list and
gen_add_list from ansible_freeipa_module to reduce the lists to the items
only that are needed to be added or removed.

The errors "already a member" and "not a member" are not ignored
anymore now while executing the comamnds.

Two new functions have been added for member management in plugins:

gen_add_list(user_list, res_list)
    Generate the add list for addition of new members.

gen_intersection_list(user_list, res_list)
    Generate the intersection list for removal of existing members.

gen_add_list should be used to add new members with action: members and
state: present. It is returning the difference of the user and res list
if the user list is not None.

gen_intersection_list should be used to remove existing members with
action: members and state: absent. It is returning the intersection of
the user and res list if the user list is not None.

tests/azure: Install community.docker Ansible collection

The test preparation failed with "the connection plugin
'community.docker.docker' was not found" in "Setup test container".

"ansible-galaxy collection install community.docker" has been added
to

  tests/azure/templates/playbook_tests.yml and
  tests/azure/templates/pytest_tests.yml

Instead o importing ipalib.errors, modules must use
ansible_freeipa_module.ipalib_errors.

Instead o importing ipalib.errors, modules must use
ansible_freeipa_module.ipalib_errors.