SonataUserBundle: Can't install Bundle

Hi,

I’ve been unable to install this on either Symfony3 or 2.8.x the whole afternoon because I am experiencing an error I have never encountered before

here is the error

 `Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - sonata-project/user-bundle 2.2.4 requires sonata-project/doctrine-extensions ~1.0 -> satisfiable by sonata-project/doctrine-extensions[1.0.0, 1.0.1, 1.0.2] but these conflict with your requirements or minimum-stability
    - sonata-project/user-bundle 2.2.3 requires sonata-project/doctrine-extensions ~1.0 -> satisfiable by sonata-project/doctrine-extensions[1.0.0, 1.0.1, 1.0.2] but these conflict with your requirements or minimum-stability
    - sonata-project/user-bundle 2.2.2 requires sonata-project/doctrine-extensions ~1.0 -> satisfiable by sonata-project/doctrine-extensions[1.0.0, 1.0.1, 1.0.2] but these conflict with your requirements or minimum-stability
    - sonata-project/user-bundle 2.2.1 requires sonata-project/doctrine-extensions ~1.0 -> satisfiable by sonata-project/doctrine-extensions[1.0.0, 1.0.1, 1.0.2] but these conflict with your requirements or minimum-stability
    - sonata-project/user-bundle 2.2.0 requires sonata-project/doctrine-extensions ~1.0 -> satisfiable by sonata-project/doctrine-extensions[1.0.0, 1.0.1, 1.0.2] but these conflict with your requirements or minimum-stability
    - Installation request for sonata-project/user-bundle ^2.2 -> satisfiable by sonata-project/user-bundle[2.2.0, 2.2.1, 2.2.2, 2.2.3, 2.2.4].`

Here’s my composer:

`"require": {
    "php": ">=5.5.9",
    "symfony/symfony": "~2.8",
    "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": "~1.3",
    "sonata-project/admin-bundle": "dev-master",
    "sonata-project/doctrine-orm-admin-bundle": "dev-master",
    "sonata-project/easy-extends-bundle": "^2.1",
    "sonata-project/doctrine-extensions": "dev-master",
    "sonata-project/user-bundle": "^2.2"
}`

I’m I missing something?