'None' as a script

The template {{None}} may be deleted in the future. Maybe it's better to use Latn instead, because I think None defaults to Latn anyway?

Why would it be deleted? "None" indicates that we don't know what the script is yet. We wouldn't want every language that we don't know the script of to be sorted into Category:Latin script languages, and we wouldn't want the confusion that would come from having what is simply unlabeled appearing to be labeled incorrectly. (And None does not default to Latn.)