See [this post](http://clubs.ya.ru/mapsapi/replies.xml?item_no=58741)
and also [documentation](https://tech.yandex.ru/maps/doc/geocoder/desc/concepts/input_params-docpage/) for the details

Sorry for unable to provide link to the english version.
Seems that changes are not reflected in the [english documentation](https://tech.yandex.com/maps/doc/geocoder/desc/concepts/input_params-docpage/) yet

Looking through the README, the only mention of the format of `coordinates` was under the MongoDB section which is all the way at the bottom of the file.

Updated description with additional details

See: http://clubs.ya.ru/mapsapi/replies.xml?item_no=56858

Update readme for :maxmind to specify that it is the legacy web services not the GeoIP2 Percision Service

Use conventional single quotes in Gemfile

GeoLite2 is a free version of a product called GeoIP2. Both use the same
format.