multi_column_transformer support (e.g. greenmask Template Record)

[thorfi]

Is your feature request related to a problem? Please describe.

We have an "address" table and a list of known address records that we use to assign for randomisation, and we would like to be able to assign multiple columns to the same address.

Describe the solution you'd like

Support for greenmask Template Record

• https://docs.greenmask.io/latest/built_in_transformers/advanced_transformers/template_record/)