add scope and kwbegin

scope is just a list of statements

lib/vool/variables.rb

@@ -0,0 +1,12 @@
+module Vool
+  module Named
+    attr_accessor :name
+    def initialize name
+      @name = name
+    end
+  end
+
+  class LocalVariable < Statement
+    include Named
+  end
+end