如何解决作曲家的需求冲突？

我正在测试Laravel Framework新的5.1版本。

而且我想安装著名的barryvdh/laravel-ide-helper软件包。

知道问题是：barryvdh/laravel-ide-helperrequireilluminate/filesystem: 5.0.x和laravel/frameworkrequire illuminate/filesystem: 5.1.x。

如何配置我的composer.json文件？

注意：我的composer.json文件中有"minimum-stability": "dev"和"prefer-stable": true。

安装时，出现以下错误：

Problem 1
    - Conclusion: remove laravel/framework 5.1.x-dev
    - barryvdh/laravel-ide-helper 2.0.x-dev requires illuminate/filesystem 5.0.x -> satisfiable by illuminate/filesystem[5.0.x-dev, v5.0.0, v5.0.22, v5.0.25, v5.0.26, v5.0.28, v5.0.4].
    - barryvdh/laravel-ide-helper v2.0.0 requires illuminate/filesystem 5.0.x -> satisfiable by illuminate/filesystem[5.0.x-dev, v5.0.0, v5.0.22, v5.0.25, v5.0.26, v5.0.28, v5.0.4].
    - barryvdh/laravel-ide-helper v2.0.1 requires illuminate/filesystem 5.0.x -> satisfiable by illuminate/filesystem[5.0.x-dev, v5.0.0, v5.0.22, v5.0.25, v5.0.26, v5.0.28, v5.0.4].
    - barryvdh/laravel-ide-helper v2.0.2 requires illuminate/filesystem 5.0.x -> satisfiable by illuminate/filesystem[5.0.x-dev, v5.0.0, v5.0.22, v5.0.25, v5.0.26, v5.0.28, v5.0.4].
    - barryvdh/laravel-ide-helper v2.0.3 requires illuminate/filesystem 5.0.x -> satisfiable by illuminate/filesystem[5.0.x-dev, v5.0.0, v5.0.22, v5.0.25, v5.0.26, v5.0.28, v5.0.4].
    - don't install illuminate/filesystem 5.0.x-dev|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem v5.0.0|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem v5.0.22|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem v5.0.25|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem v5.0.26|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem v5.0.28|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem v5.0.4|don't install laravel/framework 5.1.x-dev
    - Installation request for laravel/framework 5.1.* -> satisfiable by laravel/framework[5.1.x-dev].
    - Installation request for barryvdh/laravel-ide-helper ^2.0@dev -> satisfiable by barryvdh/laravel-ide-helper[2.0.x-dev, v2.0.0, v2.0.1, v2.0.2, v2.0.3].

我已经尝试了下面所有具有相同结果的命令...

$ composer require barryvdh/laravel-ide-helper,
$ composer require barryvdh/laravel-ide-helper:@dev --dev
$ composer require barryvdh/laravel-ide-helper --dev --update-with-dependencies

我也尝试过在composer.json文件上创建一个别名：

"require": {
    "laravel/framework": "5.1.*",
    "illuminate/filesystem": "5.1.x-dev as 5.0.28"
},

然后有这个错误：

  Problem 1
    - Installation request for barryvdh/laravel-ide-helper dev-master -> satisfiable by barryvdh/laravel-ide-helper[dev-master].
    - Conclusion: remove laravel/framework 5.1.x-dev
    - Conclusion: don't install laravel/framework 5.1.x-dev
    - barryvdh/laravel-ide-helper dev-master requires illuminate/filesystem 5.0.x -> satisfiable by illuminate/filesystem[5.0.x-dev, 5.0.28].
    - don't install illuminate/filesystem 5.0.x-dev|don't install laravel/framework 5.1.x-dev
    - don't install illuminate/filesystem 5.0.28|don't install laravel/framework 5.1.x-dev
    - Installation request for laravel/framework 5.1.* -> satisfiable by laravel/framework[5.1.x-dev].

这是我的composer.json文件：

{
    "name": "laravel/laravel",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "type": "project",
    "require": {
        "laravel/framework": "5.1.*",
        "illuminate/filesystem": "5.1.x-dev as 5.0.28"
    },
    "require-dev": {
        "phpunit/phpunit": "~4.0",
        "phpspec/phpspec": "~2.1"
    },
    "autoload": {
        "classmap": [
            "database"
        ],
        "psr-4": {
            "Portal\\": "app/"
        }
    },
    "autoload-dev": {
        "classmap": [
            "tests/TestCase.php"
        ]
    },
    "scripts": {
        "post-install-cmd": [
            "php artisan clear-compiled",
            "php artisan optimize"
        ],
        "post-update-cmd": [
            "php artisan clear-compiled",
            "php artisan optimize"
        ],
        "post-create-project-cmd": [
            "php -r \"copy('.env.example', '.env');\"",
            "php artisan key:generate"
        ]
    },
    "config": {
        "preferred-install": "dist"
    },
    "minimum-stability": "dev",
    "prefer-stable": true
}