I understand the wide-pipe/narrow-pipe distinction. I just don't like that we're forced to use the narrow-pipe ```is_domain_name``` as an intermediary step, when the wide-pipe ```validate_domain_name``` should suffice.

>I thought we were going to move all the validation functions either to a single file, or to more logical places.
Not sure what our plan here is. We definitely shouldn't move *all* of them to a single file, because many of them belong specifically to ```cydns``` objects. But others, like ```validate_domain_name```, would be appropriate to both ```cydns``` and ```cydhcp``` objects.