MVC Bootstap Config

If the structure of the ZF2 application is flattened with no modules, chances are, there is no need to use a module manager. This PR provides a MVC\Bootstrap\ConfigManager which replicates ModuleManager\ConfigListener, but does not require a ModuleManager and is not event based. 

Example usage
```php
$options = array(
    'cache_dir'            => 'data/cache',
    'config_cache_enabled' => true,
    'config_cache_key'     => 'cache-config.php',
    'config_glob_paths' => array(
       'config/autoload/{,*.}{global,local}.php',
    )
);

$cm = new ConfigManager(new ConfigOptions($options));

$cm->addConfigStaticPaths((array) $config);

//Just like ConfigListener::onLoadModulesPost
$config = $cm->loadMergedConfig(); 

$smConfig = isset($config['service_manager']) ? $config['service_manager'] : array();

$serviceManager = new ServiceManager(new ServiceManagerConfig($smConfig));
$serviceManager->setService('Config', $config);

$application = $serviceManager->get('Application');

$application->bootstrap();
```