作曲家冲突与Symfony 3

我对composer和symfony完全陌生，我已经开始了一个symfony3项目。事情进展顺利，但现在作曲家不会更新我的依赖关系。我已经搜索了3个小时的解决方案。

这是我的控制台日志：

  Problem 1
- sonata-project/admin-bundle dev-master requires sonata-project/block-bundle 3.x-dev@dev -> satisfiable by sonata-project/block-bundle[3.x-dev] but these conflict with your requirements or minimum-stability.
- sonata-project/admin-bundle dev-master requires sonata-project/block-bundle 3.x-dev@dev -> satisfiable by sonata-project/block-bundle[3.x-dev] but these conflict with your requirements or minimum-stability.
- Installation request for sonata-project/admin-bundle dev-master -> satisfiable by sonata-project/admin-bundle[dev-master].

我的composer.json需求：

    "require": {
    "php": ">=5.5.9",
    "symfony/symfony": "3.0.*",
    "doctrine/orm": "^2.5",
    "doctrine/doctrine-bundle": "^1.6",
    "doctrine/doctrine-cache-bundle": "^1.2",
    "symfony/swiftmailer-bundle": "^2.3",
    "symfony/monolog-bundle": "^2.8",
    "sensio/distribution-bundle": "^5.0",
    "sensio/framework-extra-bundle": "^3.0.2",
    "incenteev/composer-parameter-handler": "^2.0",
    "friendsofsymfony/user-bundle": "dev-master",
    "sonata-project/admin-bundle": "dev-master",
    "sonata-project/doctrine-orm-admin-bundle": "dev-master"
},

如果你能找到问题并向我解释，你将成为我的英雄！