zendservice-recaptcha install

composer.json

{
    "repositories": [
        {  
            "type": "composer",
            "url": "http://packages.zendframework.com/"
        }
    ],
    "require": {
        "php": ">=5.3.3",
        "zendframework/zend-stdlib": ">=2.0.0beta5",
        "zendframework/zend-version": ">=2.0.0beta5",
        "zendframework/zend-loader": ">=2.0.0beta5",
        "zendframework/zend-validator": ">=2.0.0beta5",
        "zendframework/zend-uri": ">=2.0.0beta5",
        "zendframework/zend-http": ">=2.0.0beta5",
        "zendframework/zendservice-recaptcha": ">=2.0.0beta5"
    }
}