[Finder] Added support for wildcard characters (GLOB patterns)

Added support for wildcard characters in the paths passed to the *in()* method. Each pattern has to resolve to at least one directory, otherwise exception is thrown (just like when path to an invalid directory is passed).

Example usage:

```php
$finder = new \Symfony\Component\Finder\Finder();
$files = $finder->files()
    ->name('validators.en.*')
    ->in(array(
        'src/Symfony/*/*/Resources/translations',
    ));

foreach ($files as $file) {
    var_dump($file->getRealPath());
}
```

Bug fix: no
Feature addition: yes
Backwards compatibility break: no
Symfony2 tests pass: yes
Fixes the following tickets: #5450
Todo: -
License of the code: MIT
Documentation PR: symfony/symfony-docs#2089