Update a group

    CLI Example:

    .. code-block:: bash

        salt '*' keystoneng.group_update name=group1 description='new description'
        salt '*' keystoneng.group_create name=group2 domain_id=b62e76fbeeff4e8fb77073f591cf211e new_name=newgroupname
        salt '*' keystoneng.group_create name=0e4febc2a5ab4f2c8f374b054162506d new_name=newgroupname

def group_update(auth=None, **kwargs):
    '''
    Update a group

    CLI Example:

    .. code-block:: bash

        salt '*' keystoneng.group_update name=group1 description='new description'
        salt '*' keystoneng.group_create name=group2 domain_id=b62e76fbeeff4e8fb77073f591cf211e new_name=newgroupname
        salt '*' keystoneng.group_create name=0e4febc2a5ab4f2c8f374b054162506d new_name=newgroupname
    '''
    cloud = get_operator_cloud(auth)
    kwargs = _clean_kwargs(**kwargs)
    if 'new_name' in kwargs:
        kwargs['name'] = kwargs.pop('new_name')
    return cloud.update_group(**kwargs)