Get the image storage directory

def appliances_path(self):
        """
        Get the image storage directory
        """
        server_config = Config.instance().get_section_config("Server")
        appliances_path = os.path.expanduser(server_config.get("appliances_path", "~/GNS3/projects"))
        os.makedirs(appliances_path, exist_ok=True)
        return appliances_path