Converting bootstrap file from procedural code to OOP

My bootstrap file contained procedural code, but after stumbling upon this answer I tried to make my bootstrap object oriented.

This is my attempt so far, and I have a feeling that I'm failing at it. I also know that some parts are not really working, because usually with procedural code the changes are made globally and not within a class' scope. I don't know how I can achieve that. Also the methods would have to be performed in order.

Could someone review my bootstrap code and how I can better the logic / usability?

I'm sorry if my code is a little bit overwhelming, but any help is highly appreciated!

Old procedural bootstrap (index.php)

# report all php errors
error_reporting(E_ALL);

# OS independent directory separator
define('DS', DIRECTORY_SEPARATOR);

# define site root path
define('ABSPATH', dirname(__FILE__) . DS);

# auto include entire config array
foreach (glob(ABSPATH . 'config' . DS . '*.php') as $configFile) {
    require $configFile;
}

# auto include all functions
foreach (glob(ABSPATH . 'functions' . DS . '*.php') as $functionFile) {
    require $functionFile;
}

# set include paths to be used for class auto loading
set_include_path(
    ABSPATH . 'core'        . PATH_SEPARATOR .
    ABSPATH . 'controllers' . PATH_SEPARATOR .
    ABSPATH . 'models'      . PATH_SEPARATOR .
    ABSPATH . 'libraries'   . PATH_SEPARATOR .
    ABSPATH . 'helpers'
);

# enable auto loading of classes with the include paths above
spl_autoload_register(
    function ($classname)
    {
        $classname = ltrim($classname, '\\');

        preg_match('/^(.+)?([^\\\\]+)$/U', $classname, $match);

        $classname = str_replace('\\', '/', $match[1]) . str_replace(['\\', '_'], '/', $match[2]) . '.php';

        require_once $classname;
    }
);

# create config object for global scope
$config = new Config($config);

# load session ini settings
foreach ($config->get('session') as $setting => $value) {
    ini_set($setting, $value);
}

session_name('sid');
session_start();

# load router
$request = new Request($_FILES, $_GET, $_POST, $_SERVER);
$router  = new Router($request);

OO index.php

require_once dirname(__FILE__) . DIRECTORY_SEPARATOR . 'core' . DIRECTORY_SEPARATOR . 'bootstrap.php';

# bootstrap the framework
$bootstrap = new Bootstrap();

# report all php errors
$bootstrap->errorReporting(E_ALL);

# OS independent directory separator
$bootstrap->directorySeparator('DS');

# define site root path
$bootstrap->rootPath('ABSPATH');

# auto include entire config array
$bootstrap->configArray('configs');

# auto include all functions
$bootstrap->functions('functions');

# set include paths to be used for class auto loading
$bootstrap->includePaths(
    array(
        'core',
        'controllers',
        'models',
        'libraries',
        'helpers'
    )
);

# enable auto loading of classes with the include paths above
$bootstrap->autoload();

# create global config object
$bootstrap->config($config);

# load session ini settings
$bootstrap->session();

# load router
$bootstrap->router();

OO Bootstrap

class Bootstrap
{
    private $ds;
    private $abspath;

    public function errorReporting($level)
    {
        error_reporting($level);
    }

    public function directorySeparator($name)
    {
        define($name, DIRECTORY_SEPARATOR);

        $this->ds = constant($name);
    }

    public function rootPath($name)
    {
        define($name, dirname(__FILE__) . '/../' . $this->ds);

        $this->abspath = constant($name);
    }

    public function configArray($directory)
    {
        foreach (glob($this->abspath . $directory . $this->ds . '*.php') as $config) {
            require $config;
        }        
    }

    public function functions($directory)
    {
        foreach (glob($this->abspath . $directory . $this->ds . '*.php') as $function) {
            require $function;
        }
    }

    public function includePaths(Array $directories)
    {
        $i        = 0;
        $numItems = count($directories);
        $paths    = '';

        foreach ($directories as $directory) {
             if(++$i !== $numItems) {
                $paths .= $this->abspath . $directory . PATH_SEPARATOR;
            } else {
                $paths .= $this->abspath . $directory;
            }
        }

        set_include_path($paths);
    }

    public function autoload()
    {
        spl_autoload_register(
            function ($classname)
            {
                $classname = ltrim($classname, '\\');

                preg_match('/^(.+)?([^\\\\]+)$/U', $classname, $match);

                $classname = str_replace('\\', '/', $match[1]) . str_replace(['\\', '_'], '/', $match[2]) . '.php';

                require_once $classname;
            }
        );
    }

    public function config()
    {
        $config = new Config([]);
    }

    public function session()
    {
        session_name('sid');
        session_start();

        foreach ($config->get('session') as $setting => $value) {
            ini_set($setting, $value);
        }
    }

    public function router()
    {
        $request = new Request($_FILES, $_GET, $_POST, $_SERVER);
        $router  = new Router($request);
    }
}