README.md in usable-2.1.3 vs README.md in usable-2.2.0

@@ -6,9 +6,10 @@
 ```ruby
 module VersionMixin
   extend Usable
   config.max_versions = 25
   config.table_name = 'versions'
+  config.model { Audit }
   
   def save_version
     "Saving #{usables.max_versions} #{usables.table_name}"
   end