Retrieve all parent keys of a given child key in Array
<p>I've been breaking my head over this one but can't seem to find a solution. I need a function that retrieves all parent keys of a given child key. So for example if I have an array like this:</p>

<pre><code>array(
    'apples' =&gt; array(
        'bananas' =&gt; array(
            'strawberries' =&gt; array(
                'fruit' =&gt; array()
            )
        )
    )
)
</code></pre>

<p>I would call the function like 'key_get_parents($key, $array)', and it would return an array with all the parent keys. In this example that would be array('apples', 'bananas', 'strawberries').</p>
