fix all existing (hash) tests

lib/sof/hash.rb

@@ -1,9 +1,12 @@
 Hash.class_eval do
   def to_sof_node(members , level)
-    node = Sof::NodeList.new(nil)
+    node = Sof::NodeList.new()
     each do |key , object|
       k = key.to_sof() + ": "
       v = members.to_sof_node( object )
+      v.data = "#{k}#{v.data}"
+      node.add v
     end
+    node
   end
 end

lib/sof/node.rb

@@ -10,17 +10,18 @@ module Sof
   end
   
   class SimpleNode < Node
-    def initialize head
-      @head = head
+    def initialize data
+      @data = data
     end
-    attr_accessor :head
+    attr_accessor :data
     def out io , level
-      io.write(head) if head
+      io.write(data) if data
     end
   end
   
-  class NodeList < Node
+  class NodeList < SimpleNode
     def initialize
+      super(nil)
       @children = []
     end
     attr_accessor  :children
@@ -31,6 +32,7 @@ module Sof
     end
 
     def out io , level = 0
+      super
       return if @children.empty?
       first = @children.first
       io.write "-"