Updated the following files in accordance to issue #316
Updated src/postorius /forms/list_forms.py , /test/test_list_forms.py , tests/mailman_api_tests/test_list_settings.py , tests/mailman_api_tests/test_user.py
These settings are obsolete as the welcome and good bye message templates can now be set via the Templates
page, and the settings should probably be removed.
Edited by saumitra_Uchiha