Use the 'base_url' instead of the 'host' for HTTP client URL (#466)

Author: childish-sambino

lib/twilio-ruby/framework/domain.rb

@@ -20,7 +20,7 @@ def request(method, uri, params = {}, data = {}, headers = {}, auth = nil, timeo
         url = uri.match(/^http/) ? uri : absolute_url(uri)
 
         @client.request(
-          @host,
+          @base_url,
           @port,
           method,
           url,