Single transforms config

[mikeknep]

Adds a new method, train_transforms, that accepts a single Transforms model config and applies it to all tables. This method accepts an optional list of tables passed as either only or ignore to limit which tables are trained. (These arguments match the optional list arguments on the Relational Trainer Connector's extract method.)

Users can include the name of a table as it appears in their db in the only|ignore argument and we will automatically extend that "request" to tables we invented from that source table (due to JSON). For example, if a purchases table had nested JSON and we ended up inventing 3 tables when we normalized that JSON data, the user can just pass the name purchases to explicitly include/exclude that table—they don't need to know the exact names of the tables we created under the hood.

This method will eventually fully replace train_transform_models, which is marked for deprecation here.

While here, updated a few of the type hints to the new style.

[pimlock]

Looks good!