Ongoing - document the history and progress of the data sets in the wiki

[jeremylang]

Goal

Make it easier for others to get up to speed on what has been learned from datasets and what is still unknown

Why

As tasks in the data team change hands over time, we've been spending a lot of time trying to re-learn. Given the amount of effort that goes into researching and understanding the laws, it's valuable to capture/share that information.

Notes

• This looks like a good wiki page for documenting the data history: https://github.com/codeforboston/clean-slate/wiki/Data:-Expungement-Analysis
• This is likely an ongoing task that everyone on the data team can contribute to as we go along.

[laurafeeney]

Added documentation by beefing up the readmes in the data/raw, data/processed, and analyses/notebooks folders.

[laurafeeney]

updated readmes in the data/raw, data/processed, and analysis/notebooks folders.