Create Endpoint to get the status of a task [3h]

[milafrerichs]

We want to get the status of a async task via django_q

For #238 we need a way for the user that uploads a file via API to get the status of the task. especially when the task finished and if there was an error.

This endpoint needs to be authenticated as well (look at the PR #247 ) do not recreate that logic.

The endpoint should probably be api/v1/tasks/:task_id

The endpoint should return a standard response:

{
  "id": ":task_id",
  "status": "running|error|success",
}

we might want to extent that, but that should work for now.