Use pytest conftest.py and drop pytest.ini

Let's replace some ugly hacks with proper pytest conftest.py hooks.
Test initialization of ipalib.api is now handled in
pytest_cmdline_main(). Pytest plugins, markers and ignores are also
moved into conftest.py. Additional guards make it possible to run tests
without ipaserver installed.

I added confcutdir to ensure that pytest does not leave our project
space. Pytest used pytest.ini or setup.py before but pytest.ini is gone.

Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Milan Kubik <mkubik@redhat.com>

ipalib/__init__.py

@@ -949,10 +949,3 @@ def create_api(mode='dummy'):
     return api
 
 api = create_api(mode=None)
-
-if os.environ.get('IPA_UNIT_TEST_MODE', None) == 'cli_test':
-    from ipalib.cli import cli_plugins
-    api.bootstrap(context='cli', in_server=False, in_tree=True, fallback=False)
-    for klass in cli_plugins:
-        api.add_plugin(klass)
-    api.finalize()