* Add draft/outline of spreadsheets
* Finish reading from Excel
* Write to Excel + consistency edits
* Add pkgs for writing Excel files
* Release the 🐧s
* Reogranize to highlight tibble/data.frame diffs
* Write again
* Add spreadsheets reference + rename_with janitor
* Move janitor to TO DO in rectangular data
* Need to load tidyverse
* Show csv file
* Add TO DO note
* Use students instead of challenge file in this chp
* Quiet down some of the redundant messages
* Add bit on reading in multiple files
* Fix up students example
* Revert back to old dataset to match spreadsheets chapter
* Fix typos
* Use US spelling
* Comments from Hadley
* Incorporate Hadley's suggestions
Co-authored-by: Hadley Wickham <h.wickham@gmail.com>