subfolder `*.csv`

Not sure if I want to do this. 

It's sketchy to have all 100+ `.csv`s in the root. They bump the readme way down to the bottom of the page. But all this is is a repo of csv files, so live with it.

Github doesn't do `--follow` in the web interface. So the last few weeks of changes will disappear from the web view. It's only a few weeks, but I think losing the history is worse than having files in the root