Merge pull request #1061 from alepore/middleware-fix

try Rack::Request if ActionDispatch::Request is not defined, fixes #1060

lib/geocoder/request.rb

@@ -80,4 +80,6 @@ end
 
 if defined?(ActionDispatch::Request)
   ActionDispatch::Request.include Geocoder::Request
+elsif defined?(Rack::Request)
+  Rack::Request.include Geocoder::Request
 end