Messy code formatting and documentation

[barrettk]

Was looking through this file and noticed a lot of the code is poorly formatted and commented.

• There is code at the bottom with library calls commented out. This shouldnt be in main
• Most of the comments were ported over from PKPDmisc, though I think they should be rewritten a bit more from a developer perspective rather than a scientist one (example)
• Code and comment indentation and new lines are odd in a few cases (example)
• The title for resample_df is just "resampling", which seems a bit lacking

I haven't looked at other scripts, but I doubt these issues are unique to this one. Would suggest running styler and fixing some other code/comment/message formatting mentioned above