title: Why my autoload.php of composer doesn't work?
body: <p>I have a project, I use Composer and i import many thing by it... i require the autoload.php in my index (the root of project) and istead Slim, Mongo, Twig work very well. But when I call a class of Respect/Validation it doens't work; if I simply use Respect/Validation the error is: </p>
  
  <p><code>Class 'Respect\Validation\Validator' not found in (path of file when i need it).</code></p>
  
  <p>if I try to require also here the autoload.php the errors are:</p>
  
  <p><code>**Warning**: require_once(vendor/autoload.php): failed to open stream: No such file or directory in (path of file when i need it)</code></p>
  
  <p><code>**Fatal error**: require_once(): Failed opening required 'vendor/autoload.php' (include_path='.;C:\xampp\php\PEAR') in (path of file when i need it)</code></p>