Is there a way to install symfony3 complete with a composer.json?
<p>all my Code is splitted into bundles, which i require with the composer.json.
Now i want to install the whole project with <code>composer install</code>, but when i try it out, the symfony folders doesn't appear and i get the following error message: </p>

<pre><code> [RuntimeException]                                                                                     
 Could not scan for classes inside "app/AppKernel.php" which does not appear to be a file nor a folder
</code></pre>

<p>Is there a way to request the symfony installation files ?</p>

<p>This is my <code>composer.json</code>:</p>

<pre><code>{
"name": "mygloriousname",
"license": "proprietary",
"type": "project",
"autoload": {
    "psr-4": {
        "": "src/"
    },
    "classmap": [
        "app/AppKernel.php",
        "app/AppCache.php"
    ]
},
"autoload-dev": {
    "psr-4": {
        "Tests\\": "tests/"
    }
},
"require": {
    "php": "&gt;=5.5.9",
    "symfony/symfony": "3.1.*",
    "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",
    "symfony/polyfill-apcu": "^1.0",
    "sensio/distribution-bundle": "^5.0",
    "sensio/framework-extra-bundle": "^3.0.2",
    "incenteev/composer-parameter-handler": "^2.0"
},
"require-dev": {
    "sensio/generator-bundle": "^3.0",
    "symfony/phpunit-bridge": "^3.0"
},
"scripts": {
    "post-install-cmd": [
        "Incenteev\\ParameterHandler\\ScriptHandler::buildParameters",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::prepareDeploymentTarget"
    ],
    "post-update-cmd": [
        "Incenteev\\ParameterHandler\\ScriptHandler::buildParameters",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
        "Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::prepareDeploymentTarget"
    ]
},
"extra": {
    "symfony-app-dir": "app",
    "symfony-bin-dir": "bin",
    "symfony-var-dir": "var",
    "symfony-web-dir": "web",
    "symfony-tests-dir": "tests",
    "symfony-assets-install": "relative",
    "incenteev-parameters": {
        "file": "app/config/parameters.yml"
    }
}
}
</code></pre>