Quick(and possibly dirty way using PHP) to convert a whole directory recursively: 
```php
<?php

$directoryPath = null;

if($argc != 2) {
	file_put_contents('php://stderr', 'Usage: php convert-directory.php <directory-path>' . "\n");
	exit(1);
}
$directoryPath = $argv[1];

if(!$directoryPath) {
	file_put_contents('php://stderr', 'Usage: php convert-directory.php <directory-path>' . "\n");
	exit(1);
} elseif(!is_dir($directoryPath)) {
	file_put_contents('php://stderr', 'Directory  "' . $directoryPath . '" not found.' . "\n");
	exit(1);
}

function convert_directory($directoryPath)
{
    foreach (glob(realpath($directoryPath) . '/*') as $path) {
        
        if (is_dir($path)) {
            convert_directory($path);
        } elseif (pathinfo($path, PATHINFO_EXTENSION) == 'php') {
            echo exec(sprintf('php ' . __DIR__ . '/convert.php %s -w', $path));
        }
    }    
}

convert_directory($directoryPath);
```
Usage: 

```
php convert-directory.php ./ZfcUser/
```