MyModel.create_table() doesn't use IF NOT EXISTS
This is now fixed -- https://github.com/coleifer/peewee/commit/2b10102d6e4d41b2d99e16be1d83fcd3983e55a0
 Awesome, thanks so much!

The docs say that `MyModel.create_table` will noop if the table already exists, but currently it raises a `sqlite3.OperationalError` instead.

It looks like the Database class method is ready for the `safe` version, but there is no way to use that from models.

It'd be nice if you could pass the `safe` boolean to `MyModel.create_table` like you can to `MyModel.drop_table`
