bug: Fixed unexpected error with invalid api key when exception-raising is not configured

[ys7i]

This PR fix the open bug issue #1657 .

Bug

If geocoder is configured with MapBox and invalid api key and always_raise doesn't contain Geocoder::InvalidApiKey, Geocoder.search will throw the following error.

/usr/local/bundle/gems/geocoder-1.8.3/lib/geocoder/lookups/base.rb:46:in `search': undefined method `map' for false:FalseClass (NoMethodError)

        results(query).map{ |r|
                      ^^^^
Did you mean?  tap

Why this happened

results(query) is evaluated as false in

geocoder/lib/geocoder/lookups/base.rb

Line 46 in 5b379a5

results(query).map{ |r|

because raise_error is called in the results method, and results returns false if always_raise doesn't contain the argument error.

[alexreisner]

This is excellent, thanks!