解决ThinkPHP5.1版本引入composer vendor扩展包的问题

版本说明

旧版本：ThinkPHP5.0新版本：ThinkPHP5.1问题：TP5.1 中取消了 Loader::import 方法以及import和vendor助手函数，全部采用命名空间和自动加载机制，导致引入类库找不到报错解决：因为“全部采用命名空间和自动加载机制”，所以对 composer/installed.json 做了修改（文字说明在下方注释中）

    {
        "name": "curl/curl",
        "version": "2.3.0",
        "version_normalized": "2.3.0.0",
        "source": {
            "type": "git",
            "url": "https://github.com/php-mod/curl.git",
            "reference": "3ad560b1fc1bbdf5c7681356ab953fb961f255e5"
        },
        "dist": {
            "type": "zip",
            "url": "https://api.github.com/repos/php-mod/curl/zipball/3ad560b1fc1bbdf5c7681356ab953fb961f255e5",
            "reference": "3ad560b1fc1bbdf5c7681356ab953fb961f255e5",
            "shasum": ""
        },
        "require": {
            "ext-curl": "*",
            "php": "^5.6 | ^7.0"
        },
        "require-dev": {
            "phpunit/phpunit": "^5.7",
            "squizlabs/php_codesniffer": "~2.1"
        },
        "time": "2020-03-19T20:07:26+00:00",
        "type": "library",
        "installation-source": "dist",
        "autoload": {
            "psr-0": {
                "Curl": "src/"
            },
            //在此处添加 files 字段，把类库文件的相对路径填入
            "files":[
                "vendor/curl/curl/src/Curl/Curl.php"
            ]
        },
        "notification-url": "https://packagist.org/downloads/",
        "license": [
            "MIT"
        ],
        "authors": [
            {
                "name": "php-curl-class",
                "homepage": "https://github.com/php-curl-class"
            },
            {
                "name": "Hassan Amouhzi",
                "email": "hassan@anezi.net",
                "homepage": "http://hassan.amouhzi.com"
            },
            {
                "name": "user52",
                "homepage": "https://github.com/user52"
            }
        ],
        "description": "cURL class for PHP",
        "homepage": "https://github.com/php-mod/curl",
        "keywords": [
            "curl",
            "dot"
        ]
    }