Remove faraday require in version.rb and define Middleware

slight cheat because of the superclass... maybe it isn't needed tho?

lib/faraday/restrict_ip_addresses/version.rb

@@ -1,5 +1,5 @@
-require 'faraday'
 module Faraday
+  class Middleware; end # so we don't have to load faraday gem to get version
   class RestrictIPAddresses < Faraday::Middleware
     VERSION = '0.2.0'
   end