Test suite failed because railtie wasn't loaded (because
Rails/ActiveRecord are stubbed out in test env). This initializes
it explicitly in test_helper before any models get defined

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

Handle responses that only have one component in the Location field, assume this is a county and so return blank city

Add PostcodeAnywhere API error handling; Map key limit exceeded, invalid key to Geocode errors and call all others as just Error

This should have been part of commit 47e11a41.