mapbox/cardboard — pull request #45 by mick (2014-09-04 22:24:09+00:00)
Title: update feature

````
cardboard.update(primary, feature, dataset, callback)
````

- [x] get current version of the feature, compute cover.
- [x] compute cover for new version of the feature.
- [x] delete any unused item (if the feature got smaller or moved)
- [x] add / update the geometries in the other items or on s3 as needed
- [x] if the feature is grow over 10k, then delete from dynamo item
- [ ] preflight check
- [ ] tests for change in index cover