Returns the register type for this plugin class.
        
        :return     <Plugin.RegisterType>

def pluginRegisterType(cls):
        """
        Returns the register type for this plugin class.
        
        :return     <Plugin.RegisterType>
        """
        default = Plugin.Type.Module
        default |= Plugin.Type.Package
        default |= Plugin.Type.RegistryFile

        return getattr(cls, '_%s__pluginRegisterType', default)