Implement ReflectionObject

[asgrim]

It's not supported currently because it requires an instance of an existing class, which means we can't currently implement...

[asgrim]

See #7

[asgrim]

We can use internal reflection API to fetch the classname. If it's set and valid, we can just reflect that class, doesn't matter if it's loaded, this is fairly easy to impl now.

[asgrim]

Note when implementing this, we would now need to be aware of runtime declared variables, e.g.:

<?php

$foo = new stdClass();
$foo->prop = 'bar';

$r = new ReflectionObject($foo);
$p = $r->getProperty('prop');
var_dump($p->isDefault()); // should be false