ipaserver: Allow configuration of test server name.

As the server name was hard coded, when running tests for ipasever
module using a server not name as 'ipaserver', the tests would fail.

This patch allows the configuration of the server name using the
variable 'ipa_server_name', and if not provided, try to infer the name
from the ansible_hostname variable, or, if not possible, defaults to
'ipaserver'.

The same behavior is applied to 'ipasever_domain', with the default
being 'ipa.test'.

group: Fix nonposix, posix and external handling and conversions

The nonposix, posix and external parameters need to be mutually
exclusive. external was missing in this list. Only one of the three
parameters can be used.

external can not be set to no/false. This results in an error now.

if nonposix is used, posix is set as not nonposix. The nonposix
parameter is not used within the code anymore..

New tests have been added to tests the addition of users with for
nonposix and posix groups. The tests for the external group is not
active due to the need of an AD.

Fixes: #528 (Error creating nonposix group)

Use execute_ipa_commands for sudocmd plugins.

config: Fix data returned from module.

When retrieving IPA configuration using ipaconfig module, a few
variables were not returning, and some data had the wrong data format.

This patch fix both issues and apply some refactoring, as data was
being retrieved from IPA API in different places using different
methods.

config: Remove unused code.

CI: pin ansible-core version for ansible-doc-test.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

Use gen_add_list and gen_intersection_list for sudocmd member handling,
to reduce the add lists to only the new and del lists only to existing
entries.

This enables to remove the ignores for "already a member" and
"not a member" errors.

Removed the definition of unused function 'gen_args()' from ipaconfig.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

This patch adds ansible-core version to 2.11 when evaluating
documentation with ansible-doc-test, so both 2.9 (ansible) and
2.11 (ansible-core) are covered when testing documentation,
along with the latest Ansible version available.

Fix documentation and usage of IPAAnsibleModule

Fix parameters used to IPAAnsibleModule.ipa_command, as a singlo list
was being used instead of a parameter list.

In the provided example for the class documentation, the parameters
passed to the `ipa_command` method were wrong, as a single list was
used instead of a parameter list.

Use execute ipa commands

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

execute_ipa_commands replces the check mode exit, the loop over the
generated commands and also in the member failure handling for modules
with member support.

The staticmethod member_error_handler is handing the default member
related failures that can occur for modules with member support.
This can simply be enabled with fail_on_member_errors=True for
execute_ipa_commands.

An exception handler is also now usable with execute_ipa_commands. In
addition to the the exception it is also getting the same user defined
arguments that the result_handler is getting.

handle_result has been renamed in result_handler and handle_result_user_args
has been renamed to handlers_user_args.

Additionally the errors list does not need to be defined in the module.
The method execute_ipa_commands is doing this internally and is also
adding error: error to handlers_user_args if the handler is having errors
in the argspec and errors is not yet set in handlers_user_args.

Tests have been added to make sure that no user args for the handler
have been set without an own result or exception handler. Also the use of
fail_on_member_errors together with a result_andler is leading to an
error.