Allow autoload.json in arbitrary directories, do not require root namespace in path/allow arbitrary path per root namespace.

[ghedipunk]

Leaving this here for review, mostly.

My use case, that prompted me to make these changes in my fork

The directory structure that I'm working with here is PSR-0-like, but not compatible with PSR-0, because it doesn't use the root namespace in any folders. (Actually, it does use the root namespace in the project's root folder, but there are a couple of directories between the root folder and the folder where autoloaded classes reside.)

My directory structure:

• /bigdumbogre -- project root. index.php lives here.
• /bigdumbogre/Resources -- web resources... images, scripts, stylesheets, etc.
• /bigdumbogre/Private -- protected by .htaccess. Also contains bootstrap.php which I will include lower with my example of how to use
• /bigdumbogre/Private/Classes -- root of autoloaded classes.
• /bigdumbogre/Private/Foundation/Configuration -- place where configuration files reside.

So, because of the project's special needs, I have edited the \Axel\Module\Library class to be a bit more configurable, and maintaining backwards compatibility by making the new constructor arguments optional.

Here's /bigdumbogre/Private/bootstrap.php, as an example of how I'm using it.

<?php

$globalBasePath = __DIR__;

require_once('Classes/External/Axel/axel.php');
$axel = new \Axel\Axel;

require_once('Classes/External/Dice/Dice.php');
$dice = new \Dice\Dice();

$axel->addModule(new \Axel\Module\PSR0('/Classes/External/Transphporm/src', '\\Transphporm'));
$axel->addModule(new \Axel\Module\Library($axel, '/Classes/Foundation/Configuration', '', $globalBasePath));

session_start();

/bigdumbogre/Private/Classes/Configuration/autoload.json for this project

{
    "include": ["../Autoloader.php"],
    "modules": {
        "\\BigDumbOgre\\Foundation\\Autoloader": []
    }
}

And /bigdumbogre/index.php that is able to get an arbitrary class

<?php

require_once('Private/bootstrap.php');

$router = $dice->create('\\BigDumbOgre\\Foundation\\Router');