Remove generator tag from Drupal 7 HTML header

If you watch the HTML generated by Drupal 7, you could see that in the header it creates a metadata tag of the generator which is used to create the website. Something like this:

<meta name="Generator" content="Drupal 7 (http://drupal.org)" />

But often, it's possible that we are intereseted in remove this mark for diferents reasons. To do this, you only have to write a little function in you theme (template.php):

function cesca_html_head_alter(&$head_elements) {

  unset($head_elements['system_meta_generator']);

}