/**
  * Returns an instance of tx_fbmagento_interface
  *
  * Singleton pattern implementation
  *
  * @param array emConf
  * @return tx_fbmagento_interface Provides a fluent interface
  */
 public static function getInstance(array $config)
 {
     if (null === self::$_instance) {
         self::$_instance = new self();
         self::$_instance->init($config);
     }
     return self::$_instance;
 }