added autovalidation (auto_validate! in your ExtendedDocument) and extracted some extlib stuff so we will soon be able to remove the dependency.

lib/couchrest/core/document.rb

@@ -1,18 +1,6 @@
-module CouchRest
-  class Response < Hash
-    def initialize(keys = {})
-      keys.each do |k,v|
-        self[k.to_s] = v
-      end
-    end
-    def []= key, value
-      super(key.to_s, value)
-    end
-    def [] key
-      super(key.to_s)
-    end
-  end
-  
+require 'delegate'
+
+module CouchRest  
   class Document < Response
     include CouchRest::Mixins::Attachments