settings.php

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Alpha Mail settings
 *
 * @package    tool_alpha_mail
 * @copyright  2018 Cameron Ball <cameron@cameron1729.xyz>
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die();

global $DB;

if ($hassiteconfig) {
    global $CFG, $DB;
    require_once($CFG->dirroot . '/admin/tool/alpha_mail/alpha_mail_message_setting.php');

    $temp = new admin_settingpage('alphamail', 'Alpha Mail');
    $temp->add(new admin_setting_heading('alphmail', 'Message', 'Messages for the boys!'));
    $temp->add(
        new alpha_mail_message_setting(
            'alphamailmessage',
            'Alpha Mail Message',
            'Message for alpha mail',
            null,
            PARAM_TEXT
        )
    );

    $ADMIN->add('server', $temp);
}