fix local assignment

was missing a method that got lost in copy/paste
also renaming to get guard to pick up tests

lib/vool/local_assignment.rb

@@ -8,6 +8,11 @@ module Vool
       from = @value.slot_definition(compiler)
       return chain_assign( Mom::SlotLoad.new(to,from) , compiler)
     end
+
+    def chain_assign(assign , compiler)
+      return assign unless @value.is_a?(SendStatement)
+      @value.to_mom(compiler) << assign
+    end
   end
 
 end