Return a list of all available services

    root
        Enable/disable/mask unit files in the specified root directory

    CLI Example:

    .. code-block:: bash

        salt '*' service.get_all

def get_all(root=None):
    '''
    Return a list of all available services

    root
        Enable/disable/mask unit files in the specified root directory

    CLI Example:

    .. code-block:: bash

        salt '*' service.get_all
    '''
    ret = _get_systemd_services(root)
    ret.update(set(_get_sysv_services(root, systemd_services=ret)))
    return sorted(ret)