Add support for _gat._anonymizeIp();

I just implemented the needed functionality and tested it, here's the code:

googleanalytics.module, please add in line 168 of V 6.2.2

    $anonymize_ip = variable_get('googleanalytics_anonymizeip', 0);
    if(!empty($anonymize_ip)){
      $script .= '_gat._anonymizeIp();';
    }

googleanalytics.admin.inc, please add in line 251 of V 6.2.2

    $form['advanced']['googleanalytics_anonymizeip'] = array(
    '#type' => 'checkbox',
    '#title' => t('Anonymize visitors IP address'),
    '#default_value' => variable_get('googleanalytics_anonymizeip', 0),
    '#description' => t('Tell Google Analytics to anonymize the information sent by the tracker objects by removing the last octet of the IP address prior to its storage. Note that this will slightly reduce the accuracy of geographic reporting.')
  );

If I shell add it to the dev version, it would be nice if you could provide me with CVS access. Furthermore I could add test cases for this functionality.

You may find the patch file for the latest Head revision attached.

Sorry, patch here!

Please check it first.

I think it is not a good idea to add it as custom js because basic users won't understand. Why not add a checkbox?

In some countries like Germany for example collecting all this user information is not allowed by law. In my oppinion this option will clearly be used!

Why can it only be used with async tracking in your oppinion? I don't think so!

Quote from Google: "For async tracking, use the _gaq global object instead." - We don't!
But maybe I am wrong?

Well there are laws concerning this topic, but at the moment they just don't prosecute.
The point is that you are not allowed to save personal data if it is not explicitly needed, but however... this should not be topic.

All in all it is a good feature, but I agree, not that important to be critial.

Why should it not be added to V6.x.2x.dev? (and 3.x.dev of course)?