Include latest version of jQuery on a website.

script.includer.js

(function(d, url) { 
   var h = d.getElementsByTagName('head')[0],
       s = d.createElement('script');
  
   s.src = url; 
   s.onload = function() { 
      console.log('loaded %s', url); 
   };
   
   h.appendChild(s);  

}(document, 'http://code.jquery.com/jquery-git.js'/*prompt('url?')*/));