Add Ubercart Google Base Integration Settings to Vertical Tabs

Adding the integration settings to verticals tabs cleans up the product form nicely and is consistent with the other Ubercart fieldsets (Product Information/Shipping Settings).

We just need to add the following to the $form['uc_gbase'] inside the uc_gbase_form_alter:

        '#group' => 'additional_settings',

This gives us:

    $form['uc_gbase'] = array(
        '#type' => 'fieldset',
        '#title' => t('Ubercart Google Base Integration Settings'),
        '#collapsible' => TRUE,
        '#collapsed' => FALSE,
        '#tree' => TRUE,
        '#group' => 'additional_settings',
    );