Use new APIv2 paginated team list. Fixes #106

My first major contribution, so someone should definitely look over it closely.

Some things I'm concerned about:
- The fact that the API returns page sizes of 500 is currently hardcoded. Is there a place we put constants like this?
- `getSimpleTeamsInRange()` makes multiple API calls, each of which may have a different `APIResponse.CODE`. I don't think anything else we have follows this pattern. Right now I just manually set it to `UPDATED`. Is that okay?
The case to JsonObject is redundant - the parser methods will do that