* Handle Geocoder::OverQueryLimitError gracefully.

Geocoder::OverQueryLimitError errors were not being generated correctly, and the response was coming back empty but with no indication.

This changes the behavior slightly so that unknown errors are also returned.

* Add error handling tests

* Remove unnecessary config in tests

* Add support for DB-IP.com geocoding service

* Added support for https with paid accounts

* Use `use_https` to distinguish between paid/unpaid API usage

* Clean rubocop warnings