Regression: node module no longer returns nid with drupal_execute() node creation.

When a node, taxonomy term, or taxonomy vocabulary was saved, the nid/vid/tid of the created object was added to the $form_state to allow other modules a chance to operate on them. This is also essential when using drupal_execute(); otherwise, there's no way to determine the nid of the node that was created.

This behavior was accidentally lost during a refactoring at some point in the past couple of months. The attached patch adds the line back in and also fixes a minor error in the drupal_execute() PHPdoc. Without it, the code snippet generates errors.