Unzip Gmail attachments

```js
function unzipGmail(){
  var message = GmailApp.getMessageById('15ea48eff1160e89');
  var blobs = message.getAttachments()[0].copyBlob();
  var data = Utilities.unzip(blobs);
  data.forEach(function(blob){
    DriveApp.createFile(blob);
  });
}
```