structure renaming issues

[sarangtc]

the given "class.tree.php" and "index.php" have the issue that not all items in structure can be customized.

To fix:
possibly add function to class:
public function get_options($id, $recursive = false) {
return $this->options;
}

and add following lines before first switch:
$options = $fs->get_options();
$nm = $options['data'][0];

and replace the following:
$v['id']
with
$v[$options['structure']['id']]

$v['rgt']
with
$v[$options['structure']['right']]

$v['lft']
with
$v[$options['structure']['left']]

'nm'
with
$nm

[sarangtc]

I think the above will fix renaming anything EXCEPT 'id' => 'id' and the 'position' => 'pos' elements of structure
although I can't find any direct mentions of 'pos' in the class or the index.php