Allows to configure the Administration Area customer pages before they are displayed.
In the event handler you can update the back-end controller properties. Use it for example
to add custom filters for the customers list.
public function subscribeEvents()
{
Backend::$events->addEvent('shop:onConfigureCustomersPage', $this, 'configure_customers_page');
}
public function configure_customers_page($controller)
{
// Do something
}