alphagov/backdrop — pull request #332 by roc (2014-07-29 11:47:23+00:00)
Title: Bring back json objects for the `_status/data-sets` endpoint

Looks a bit like

```
{
"data_sets": [
{
"last-updated": null,
"max-age-expected": 200,
"name": "view_driving_record_fooo",
"seconds-out-of-date": null
}
],
"message": "All data_sets are in date",
"status": "ok"
}
```
- Changes the conditions for being out-of-date
- If it's never been updated, we can assume that the data-set isn't ready for general use, as there's likely nothing in it.
- This can be subject to discussion, but my hunch is this is going to be the simplest way to maintain this
- Returns full data-set status objects for both in-date and out-of-date data-sets.
- We can mod the status endpoint to always return both, or just one, or just the other, depending on need.
- Again, a hunch, but I feel we should be able to see how in-date something is as well as how out-of-date it is.