fix true false and nil constant

going from mom to parfait
basics in place, more ripples to fix

lib/mom/instruction/basic_values.rb

@@ -29,16 +29,25 @@ module Mom
     end
   end
   class TrueConstant < Constant
+    def to_parfait(compiler)
+      Parfait.object_space.true_object
+    end
     def ct_type
       Parfait.object_space.get_class_by_name(:TrueClass).instance_type
     end
   end
   class FalseConstant < Constant
+    def to_parfait(compiler)
+      Parfait.object_space.false_object
+    end
     def ct_type
       Parfait.object_space.get_class_by_name(:FalseClass).instance_type
     end
   end
   class NilConstant < Constant
+    def to_parfait(compiler)
+      Parfait.object_space.nil_object
+    end
     def ct_type
       Parfait.object_space.get_class_by_name(:NilClass).instance_type
     end
@@ -48,6 +57,11 @@ module Mom
     def initialize(value)
       @value = value
     end
+    def to_parfait(compiler)
+      value = Parfait.new_word(@value)
+      compiler.add_constant(value)
+      value
+    end
     def ct_type
       Parfait.object_space.get_class_by_name(:Word).instance_type
     end