No redirect option

This partially fixes #429. I know that tests are failing, but I need some help to setup tests on OS X. 

```php
<?php
// LiipImagineBundle/Tests/Functional/Controller/ImagineControllerTest.php
$this->webRoot = self::$kernel->getContainer()->getParameter('kernel.root_dir').'/web';
$this->cacheRoot = $this->webRoot.'/media/cache';
$this->filesystem = new Filesystem;
$this->filesystem->remove($this->cacheRoot);
```
This generates URL to unexisting folder, maybe some one can give me some points?