remove no longer used ajax.php

lib/plugins/acl/ajax.php

-<?php
-/**
- * AJAX call handler for ACL plugin
- *
- * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
- * @author     Andreas Gohr <andi@splitbrain.org>
- */
-
-if(!defined('DOKU_INC')) define('DOKU_INC',dirname(__FILE__).'/../../../');
-require_once(DOKU_INC.'inc/init.php');
-//close session
-session_write_close();
-
-global $conf;
-global $ID;
-global $INPUT;
-
-//fix for Opera XMLHttpRequests
-$postData = http_get_raw_post_data();
-if(!count($_POST) && !empty($postData)){
-    parse_str($postData, $_POST);
-}
-
-if(!auth_isadmin()) die('for admins only');
-if(!checkSecurityToken()) die('CRSF Attack');
-
-$ID    = getID();
-
-/** @var $acl admin_plugin_acl */
-$acl = plugin_load('admin','acl');
-$acl->handle();
-
-$ajax = $INPUT->str('ajax');
-header('Content-Type: text/html; charset=utf-8');
-
-if($ajax == 'info'){
-    $acl->_html_info();
-}elseif($ajax == 'tree'){
-
-    $dir = $conf['datadir'];
-    $ns  = $INPUT->str('ns');
-    if($ns == '*'){
-        $ns ='';
-    }
-    $ns  = cleanID($ns);
-    $lvl = count(explode(':',$ns));
-    $ns  = utf8_encodeFN(str_replace(':','/',$ns));
-
-    $data = $acl->_get_tree($ns,$ns);
-
-    foreach(array_keys($data) as $item){
-        $data[$item]['level'] = $lvl+1;
-    }
-    echo html_buildlist($data, 'acl', array($acl, '_html_list_acl'),
-                        array($acl, '_html_li_acl'));
-}
-