<!--- Verify first that your improvement is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
group module return values are undocumented.
<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
group
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.0
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/aschultz/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.3 (default, Apr 09 2019, 05:18:21) [GCC]
```
from __future__ import absolute_import, division, print_function
__metaclass__ = type
ANSIBLE_METADATA = {'metadata_version': '1.1',
                    'status': ['stableinterface'],
                    'supported_by': 'core'}
DOCUMENTATION = '''
---
module: group
version_added: "0.0.2"
short_description: Add or remove groups
requirements: