Define the available data frames

[mboyas-mitre]

https://github.com/mboyas-mitre/GrowthViz/blob/7ababcad6dd008e326bb88575df6674fbbec88e8/GrowthViz-adults.ipynb#L2464

I don't remember what all of these data frames are, and there are a bunch in here like _8 which mean nothing to me. Recommendation to add a key.