Upload the data used

[kevinheavey]

This material appears to have outlived the data sources used. For example https://www.transtats.bts.gov/DownLoad_Table.asp doesn't work, and the weather data isn't working for me either. Perhaps you (or anyone else) might upload copies of the data to this repo if you still have them?

[jrybicki-jsc]

I think I have fixed the airline data, you can check my fork:

https://github.com/jrybicki-jsc/effective-pandas/blob/master/modern_1_intro.ipynb

(the old pandas functions like ix won't work)