ZF3 Override ServiceManager Config

override.php

protected function overrideServiceManagerConfig(ServiceManager $sm, array $appendConfig)
{
	$globalConfig = $sm->get('Config');
	$allConfig = \Zend\Stdlib\ArrayUtils::merge($globalConfig, $appendConfig);

	// set Config service, service manager can't operate without it
	$sm->setAllowOverride(true);
	$sm->setService('Config', $allConfig);
	$sm->setAllowOverride(false);
}