Prisma

Documentation states "Files can be also uploaded and modified by using queries and mutations from the Simple API or the Relay API": <https://www.graph.cool/docs/reference/platform/file-management-eer4wiang0/#file-management-with-the-client-apis>

But there's no information on how to achieve this. How can it be done?

I tried 
```
mutation {
  createFile(
    name: "test"
  ) {
    name
  }
}
```

But it yields 

```
{
  "data": {
    "createFile": null
  },
  "errors": [
    {
      "message": "Whoops. Looks like an internal server error. Please contact us in Slack (<https://slack.graph.cool>) and send us your Request ID: cj1m4p6ydbikf01286t2im93r",
      "requestId": "cj1m4p6ydbikf01286t2im93r",
      "path": [
        "createFile"
      ],
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ]
    }
  ]
}
```

Hey, this is currently not yet supported by neither Apollo nor Relay. We're already working on a solution here. I'll update the docs to reflect this.