Modifica el require con el siguiente,
Código JSON:
Ver original"require": {
"php": ">=5.3.3",
"symfony/symfony": "2.1.*",
"doctrine/orm": ">=2.2.3,<2.4-dev",
"doctrine/doctrine-bundle": "1.0.*",
"twig/extensions": "1.0.*",
"symfony/assetic-bundle": "2.1.*",
"symfony/swiftmailer-bundle": "2.1.*",
"symfony/monolog-bundle": "2.1.*",
"sensio/distribution-bundle": "2.1.*",
"sensio/framework-extra-bundle": "2.1.*",
"sensio/generator-bundle": "2.1.*",
"jms/security-extra-bundle": "1.2.*",
"jms/di-extra-bundle": "1.1.*",
"friendsofsymfony/user-bundle": "dev-master",
"propel/propel-bundle": "1.1.x-dev",
"phing": "master",
"TypehintableBehavior": "master",
"white-october/pagerfanta-bundle": "dev-master",
"doctrine/doctrine-fixtures-bundle": "dev-master",
"knplabs/knp-menu-bundle": "dev-master",
"cedriclombardot/admingenerator-generator-bundle": "dev-master",
"cedriclombardot/admingenerator-activeadmintheme-bundle": "dev-master",
"cedriclombardot/admingenerator-user-bundle": "dev-master"
}
en relación a tu pregunta, no entiendo a que te refieres exactamente.
Saludos.