Display notification if newer version is available.

This is done using asynchronous javascript so it should not block any
actions.

main.php

@@ -14,6 +14,7 @@ require_once './libraries/common.inc.php';
 $GLOBALS['js_include'][] = 'colorpicker/js/colorpicker.js';
 $GLOBALS['js_include'][] = 'main_custom_color.js';
 $GLOBALS['js_include'][] = 'jquery/jquery-ui-1.8.custom.js';
+$GLOBALS['js_include'][] = 'jquery/jquery.sprintf.js';
 
 // Handles some variables that may have been sent by the calling script
 $GLOBALS['db'] = '';