I would highly highly prefer not naming a script after a language feature - `placeholder` doesn't indicate anything about what its contents are used for (same with `mixins`, but I think we talked about that). A project organized around usage groups rather than implementation details is generally much easier to learn/use, and I'd like to keep Sassquatch moving in that direction.

also, `placeholders` is ambiguous because it's also the name of HTML input placeholder text, which these styles are not related to.