Docstrings missing in some files

[Deborah Barnard]

Is your feature request related to a problem? Please describe.
For the autogenerated API docs (https://docs.capeprivacy.com/pythonv1/readme/), we end up with some blank pages due to missing docstrings, and some of the pages are quite sparse on examples.

Describe the solution you'd like
Add the docstrings

Describe alternatives you've considered
Don't include the pages in the docs - let me know if that would make more sense

Additional context
Current blank pages:
https://docs.capeprivacy.com/pythonv1/cape_privacy.pandas/dtypes/
https://docs.capeprivacy.com/pythonv1/cape_privacy.spark/dtypes/

Current pages that could use more info/examples to bring them to the same level as similar pages:
https://docs.capeprivacy.com/pythonv1/cape_privacy.pandas/transformations/column_redact/
https://docs.capeprivacy.com/pythonv1/cape_privacy.pandas/transformations/row_redact/

[jvmncs]

The docs mentioned above have been moved to Github.