static message chain

Rewrote Message + frame, only static linked list needed, not dynamic
frames either

lib/parfait/message.rb

@@ -2,14 +2,27 @@
 # A message is what is sent when you invoke a method. Args and stuff are packed up in to a Message
 # and the Message is sent to the receiver.
 
+# Part of the housekeeping (see attributes) makes messages a double linked list (next_message and
+#  caller) , and maybe surprisingly this means that we can create all messages at runtime
+# and link them up and never have to touch that list again.
+# All the args and receiver data changes, but the list of messages stays constant.
+
 module Parfait
   class Message < Object
-
     def initialize next_m
       @next_message = next_m
+      @frame = Frame.new()
+      @caller = nil
       super()
     end
 
+    attr_reader :next_message , :frame , :caller # aka prev_message
+    attr_reader :receiver ,  :return_address , :return_value , :method
+
+    def set_caller caller
+      @caller = caller
+    end
+
     def get_type_for(name)
       index = @layout.get_index(name)
       get_at(index)