Now it is necessary to specify which service is being used:
  Geocoder.configure(:maxmind => {:service => ...})
where '...' is one of: < :country | :city | :city_isp_org | :omni >

If you do this:

  Geocoder::Query.new("Kremlin, Moscow", :params => {:language => "ru"})

you should get a response in Russian ("ru") regardless of the value set
in Geocoder.configure(...).

Either do it consistently across Ruby versions, or don't do it at all.
Plus, it didn't seem to work.

Need to determine how necessary this encoding is, and how to do it
properly in 1.8.7.

Also add test for method presence in all lookups.

This code appears to be copied from the Freegeoip lookup, where it is
undesirable to begin with.

Cache is now lookup-specific.

Make Geocoder.configure accept a hash (now preferred) and add
Geocoder.config method (for reading config). Deprecate old syntax.

instead of instance variables.