Too Many API Requests

[jagreenwood]

Currently the code in this package performs 1 API request per item in the feature list to get its vote count.
I understand why, because that is how countapi works/ed. Since this project seems to be actively seeking a replacement API, it would be a good time to do better.

A couple of naive thoughts/options:

1. Decouple API calls from this package. Give consumer full control.
2. Refactor to support an endpoint that fetches a feature list with counts in addition to 1 request per item.
3. Implement a server app. Maybe RoadmapBackend could be updated to maintain features and support fetching a list.