Javascript files includes in footer

1. Create a new file called footer.php in /libraries/joomla/document/html/renderer/ directory:

2. In /libraries/joomla/document/document.php add after

   public $_scripts = array();
   this
   public $_footer_scripts = array();

3. Add method addFooterScript() after the addScript() method

   function addFooterScript($url, $type = "text/javascript", $defer = false, $async = false) {
   	$this->_footer_scripts[$url]['mime'] = $type;
   	$this->_footer_scripts[$url]['defer'] = $defer;
   	$this->_footer_scripts[$url]['async'] = $async;
   	return $this;
    }

4. In index.php in you template folder add just before the tag
   

   <jdoc:include type="footer" />
   

5. Done!
   Now in layouts inside your template's folder you can use the following code to add javascript files to footer:

   $doc =& JFactory::getDocument();
   $doc->addFooterScript('JavaScript_File_Path.js');
   

TODO : check for updates...