start a new ruby layer to do the to_vool conversion

the "normalization" is getting more and more complicated and is not tested
And it seems i really don't like working with the untyped ast

lib/ruby/class_statement.rb

@@ -0,0 +1,28 @@
+module Ruby
+  class ClassStatement < Statement
+    attr_reader :name, :super_class_name , :body
+
+    def initialize( name , supe , body)
+      @name , @super_class_name = name , supe
+      case body
+      when MethodStatement
+        @body = Statements.new([body])
+      when Statements
+        @body = body
+      when nil
+        @body = Statements.new([])
+      else
+        raise "what body #{body}"
+      end
+    end
+
+    def normalize
+      meths = body.statements.collect{|meth| meth.normalize}
+      ClassStatement.new(@name , @super_class_name, Statements.new(meths) )
+    end
+
+    def to_s(depth = 0)
+      at_depth(depth , "class #{name}" , @body.to_s(depth + 1) , "end")
+    end
+  end
+end