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

Use faster ruby methods

See: https://speakerdeck.com/sferik/writing-fast-ruby

Fixes OID warnings when using PostgreSQL

Postgres correctly identifies OIDs when BEARING and DISTANCE contain
numerical values. It fails to identify OID for a NULL type.

This patch explicitly sets an OID type for NULLs when running in
PostgreSQL environment.

Add table_name to AR geocoded and not_geocoded scopes

Add :postcode_anywhere_uk lookup.

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

Limit maxmind local subselect query to reduce cost

Since we only want to select one IP block anyway, limiting this query
reduces the query cost from (cost=22531.65..22539.67 rows=1 width=31)
to (cost=0.53..8.54 rows=1 width=31)

IPv6 loopback ip ::1 should be detected as a valid loopback ip..