Load the chalice config file from the project directory.

        :raise: OSError/IOError if unable to load the config file.

def load_project_config(self):
        # type: () -> Dict[str, Any]
        """Load the chalice config file from the project directory.

        :raise: OSError/IOError if unable to load the config file.

        """
        config_file = os.path.join(self.project_dir, '.chalice', 'config.json')
        with open(config_file) as f:
            return json.loads(f.read())