For each VPN file in directory/vpns, create a new configuration
    file and all the associated directories

    Note: the expected directory structure is
    args.directory
    -----vpns (contains the OpenVPN config files
    -----configs (contains the Centinel config files)
    -----exps (contains the experiments directories)
    -----results (contains the results)

    :param directory:

def create_config_files(directory):
    """
    For each VPN file in directory/vpns, create a new configuration
    file and all the associated directories

    Note: the expected directory structure is
    args.directory
    -----vpns (contains the OpenVPN config files
    -----configs (contains the Centinel config files)
    -----exps (contains the experiments directories)
    -----results (contains the results)

    :param directory:
    """
    logging.info("Starting to create config files from openvpn files")

    vpn_dir = return_abs_path(directory, "vpns")
    conf_dir = return_abs_path(directory, "configs")
    os.mkdir(conf_dir)
    home_dirs = return_abs_path(directory, "home")
    os.mkdir(home_dirs)
    for filename in os.listdir(vpn_dir):
        configuration = centinel.config.Configuration()
        # setup the directories
        home_dir = os.path.join(home_dirs, filename)
        os.mkdir(home_dir)
        configuration.params['user']['centinel_home'] = home_dir
        exp_dir = os.path.join(home_dir, "experiments")
        os.mkdir(exp_dir)
        configuration.params['dirs']['experiments_dir'] = exp_dir
        data_dir = os.path.join(home_dir, "data")
        os.mkdir(data_dir)
        configuration.params['dirs']['data_dir'] = data_dir
        res_dir = os.path.join(home_dir, "results")
        os.mkdir(res_dir)
        configuration.params['dirs']['results_dir'] = res_dir

        log_file = os.path.join(home_dir, "centinel.log")
        configuration.params['log']['log_file'] = log_file
        login_file = os.path.join(home_dir, "login")
        configuration.params['server']['login_file'] = login_file
        configuration.params['user']['is_vpn'] = True

        configuration.params['server']['verify'] = True
        configuration.params['experiments']['tcpdump_params'] = ["-i", "tun0"]

        conf_file = os.path.join(conf_dir, filename)
        configuration.write_out_config(conf_file)