Implement class instance variables

as they are just the type of the meta_class, that was relatively simple.
I feel this is what oo is meant to be, instance variables and methods for the objects, and since classes are objects, for them too.
Class variables seem like a design mistake, weird scoping rules and no data hiding (left as an exercise to the reader)

lib/vool/class_method_expression.rb

@@ -11,7 +11,6 @@ module Vool
       raise "not meta" unless clazz.class == Parfait::MetaClass
       raise( "no class in #{self}") unless clazz
       method = clazz.add_method_for(name , make_arg_type , make_frame , body )
-#VoolMethod
       compiler = method.compiler_for(clazz.instance_type)
       each {|node| raise "Blocks not implemented" if node.is_a?(LambdaExpression)}
       compiler