HTML-style attributes

In Haml HTML-style aatributes work just like attribute hashes.
So this:

``` haml
%html(xmlns="http://www.w3.org/1999/xhtml")
```

should result in this

``` html
<html xmlns="http://www.w3.org/1999/xhtml"></html>
```

Instead phphaml outputs this:

``` php
<html<?php $this->writeAttributes(array ('class' => 'w3 org')); ?>>
  <?php echo ; ?>
```
