Does not detect `use $foo as $bar`

[Benjamin Eberlei]

The following will be detected as error:

use Foo as Bar;

class Foo extends Bar
{
}

[Bastian Hofmann]

This actually should work and should be covered as we are doing something like this a few times as well. I'll have a short look at it in the next days. Probably just a tiny thing that can be fixed or added without rewriting it completely to use php-parser