Added an option to enable embed:// prefixing of urls that you require passing.

```php

$config = array('use_embed_prefix' => true);
$text = 'http://dailymotion.com/video/xp30q9_bmw-serie3-2012-en-mexico_auto embed://vimeo.com/groups/shortfilms/videos/66185763  http://youtube.com/watch?v=J---aiyznGQ';
$embera = new \Embera\Embera($config);
echo $embera->autoEmbed($text)

```

outputs

```html
http://dailymotion.com/video/xp30q9_bmw-serie3-2012-en-mexico_auto <iframe src="http://player.vimeo.com/video/66185763" width="1280" height="536" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowFullScreen></iframe>  http://youtube.com/watch?v=J---aiyznGQ
```