Improve web error

lib/shotengai/web_error.rb

@@ -2,7 +2,7 @@ module Shotengai
   class WebError < RuntimeError
     attr_accessor :message, :code, :status
     def initialize message, code, status
-      super()
+      super(message)
       @message, @code, @status = message, code, status
     end
   end