Pin package versions, add pyproject.toml, uv instructions. Close #217

Remove outdated code example, close #164

Update notebooks for pandas 2.0.0, close #170

Upload cleaner notebook files without internal build toolchain instructions

Update COPYING

Update notebooks in advance of publication

README improvements

Simplifying datasets

Add fec.parquet

Add newline

Delete unused files, update README a little bit

Unpin requirements

Add Date column to spx.csv

Recode data as utf-8

Recode movies.dat as utf-8 from ISO-8859-1