[WIP] Fixer that converts old style constructors into __construct()

Please share your thoughts on this fixer.

I need to implement ignoring of oldstyle constructors in namespaced classes (added in PHP 5.3.3), and the fixer should be done.

I'm wodndering if there are some more rules that i should consider in this fixer?
No idea why anyone would write code like this, but we should still support it since it's valid:

```php
function
/* Constructor */
  __construct
/** @param mixed $foo */
    ($foo)

{}
```