Ninetydf

- Fix `louis_gattone` id

- Add `person_id_x` and `person_id_y` cols
- Combine duplicate `Tiffany & Ronald` ids

- Add TLR data

- Fix `Jason & Cássia` ids
- Add test to ensure ids are normalized
- Add docs on use without `pandas`

- Fix `michael_juliana` data
- Add test assertion for couple name format
- Add `Couple` and `Season` dataclasses
- Make pandas an optional dependency
- Add `couples_list` and `seasons_list`
- Rename `couples` and `seasons` to `couples_df` and `seasons_df`

- Added HEA data
- Added TOW data
- Added `appearance_id` and `season_id` columns
- Converted `show_id` values to uppercase