Should not change migrations

[softwaregravy]

Migrations which have been committed and deployed should be effectively immutable. Rather than editing past migrations, it would be better to create a new migration which renames the table. As is, renaming a model cannot be used in a production system.

[jcrisp]

Thanks for the suggestion, it sounds like a highly useful improvement. Would you be interested in writing a (small) PR for it? I'd suggest making it an option based on a command line switch, as there are times when you'd want to rename directly and others where you'd want a migration.