我想将我的cakephp 2应用程序升级到cakephp 3，但遇到了问题。
我使用的是PHP 7.1和Ubuntu 16以及nginx / 1.10.0（Ubuntu）。
我得到了以下错误信息...
Fatal error: Cannot declare class lib\Cake\Core\App because the name is already in use in /usr/share/nginx/html/web/lib/Cake/Core/App.php on line 70
我正在关注这个页面：https://github.com/cakephp/upgrade
首先，我使用以下命令：
bin/cake upgrade locations [path]
bin/cake upgrade namespaces [path]
bin/cake upgrade app_uses [path]
bin/cake upgrade rename_classes [path]
bin/cake upgrade rename_collections [path]
bin/cake upgrade method_names [path]
bin/cake upgrade method_signatures [path]
bin/cake upgrade fixtures [path]
bin/cake upgrade tests [path]
bin/cake upgrade i18n [path]
bin/cake upgrade skeleton [path]
bin/cake upgrade prefixed_templates [path]
更多细节:
我的php版本是（输出php -v的结果）:
PHP 7.1.0-5+deb.sury.org~xenial+1 (cli) ( NTS )
Copyright (c) 1997-2016 The PHP Group
Zend Engine v3.1.0-dev, Copyright (c) 1998-2016 Zend Technologies
with Zend OPcache v7.1.0-5+deb.sury.org~xenial+1, Copyright (c) 1999-2016, by Zend Technologies
with Xdebug v2.5.0, Copyright (c) 2002-2016, by Derick Rethans
我的Ubuntu版本（lsb_release -a 的输出）为：
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.1 LTS
Release: 16.04
Codename: xenial