class name changed from VShowOption into IVOptionable

// ----------------------------------------------------------------------------
// IVShowOption
// ----------------------------------------------------------------------------
class IVShowOption
{
public:
  virtual void addOptionWidget(QLayout* layout) = 0;
  virtual bool showOption(QDialog* dialog)      = 0;
  virtual void saveOption(QDialog* dialog)      = 0;
};

// ----------------------------------------------------------------------------
// IVOptionlable
// ----------------------------------------------------------------------------
class IVOptionlable
{
public:
  virtual QDialog* createOptionDlg() = 0;
  virtual void     addOptionWidget(QLayout* layout) = 0;
  virtual bool     showOptionDlg(QDialog* dialog) = 0;
  virtual void     saveOptionDlg(QDialog* dialog) = 0;
};