dangerAll specification when updating all raindrops

Hello. I'm having a problem sending a put request to all my raindrops (collection id = 0).

```
{
    "result": false,
    "error": 400,
    "errorMessage": "to update all raindrops please specify *dangerAll*"
}
```

Where do I specify this dangerAll? I tried adding it as ID parameter, body, etc. No avail. Thank you!