Autoloader can load a class file more than once

I found this error because i named a model’s class differently than its filename on accident.

If you have a model named Test.php and inside there is no class Test {} and you call class_exists('\Namespace\Model\Test') more than one time, the autoloader will attempt to load the file a second time, throwing a duplicate class error.

To fix the issue i changed:

/EllisLab/ExpressionEngine/Core/Autoloader.php:100

from:

if (file_exists($class_path))
    {
     require $class_path;
     return;
    }

to:

if (file_exists($class_path))
    {
     require_once $class_path;
     return;
    }