public static function getAuthKey($username, $password, $nonce)
    {
        return md5($nonce . $username . md5($username . ':mongo:' . $password));
    }
public static function getAuthKey($username, $password, $nonce)
    {
        return md5($nonce . $username . md5($username . ':mongo:' . $password));
    }
public static function getAuthKey ( $ username , $ password , $ nonce ) { return md5 ( $ nonce . $ username . md5 ( $ username . ':mongo:' . $ password ) ) ; }
Generates auth. key
@param  string $username Username
@param  string $password Password
@param  string $nonce Nonce
@return string           MD5 hash
Generates auth . key