[NFR]Config Support for reading PHP files

config.php
```php
<?php

return array(
		"database" => array(
			"adapter" => "mysql",
			"host" => "localhost",
			"username" => "user",
			"password" => "passwd",
			"name" => "demo"
		),
	);
```
Use
```php
$config = new Phalcon\Config('../app/config/config.php');
```