##### SUMMARY
gitlab_project_variable: support hidden/protected variables

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
gitlab_project_variable
api_token: secret_access_token
    project: markuman/dotfiles
    purge: false
    vars:
      ACCESS_KEY_ID: abc123
      SECRET_ACCESS_KEY: 321cba
- name: Delete one variable
  gitlab_project_variable:
    api_url: https://gitlab.com
    api_token: secret_access_token
    project: markuman/dotfiles
    state: absent
    vars:
      ACCESS_KEY_ID: abc123
'''
RETURN = '''
project_variable:
  description: Four lists of the variablenames which were added, updated, removed or exist.
  returned: always
  type: dict
  contains:
    added:
      description: A list of variables which were created.
      returned: always
      type: list
      sample: "['ACCESS_KEY_ID', 'SECRET_ACCESS_KEY']"
    untouched:
      description: A list of variables which exist.
      returned: always
      type: list