Address review

[wright13]

Created vignette from paper excerpt and added unit tests. Unit test coverage is ~47%, but I didn't want to write a bunch of tests for the functions in updateR.R since I am actively reworking that code. Tidyverse test coverage is 53%, so I think we're in okay shape for now.

[RobLBaker]

While I generally like the idea of including the paper in the package, I haven't been able to get the .rmd to properly knitt previously, especially getting multiple author and institution attributions (at least to .pdf). I wonder if it might be better to wait until the paper is published and then add the .pdf to the package?

[wright13]

@RobLBaker so this is how tidyverse is doing it: https://github.com/tidyverse/tidyverse/tree/main/vignettes. I think we'll have an easier time knitting to html than to pdf, if we do want to include the paper in the pkgdown site and/or as a vignette.
I do agree with the reviewer comment (openjournals/joss-reviews#8066 (comment)) that if folks are trying to learn about the package through the vignette instead of the readme/github pages, they currently aren't getting the information they need.
My thinking was that adding some info from the paper to the vignette is an easy way to make it more usable in the short term, and then once the paper is published we may want to talk more in depth about what belongs in the readme vs vignettes vs both, and also consider offering the full paper as a vignette. That said, I'm not tied to that strategy and we can definitely leave the vignette out for now if you'd rather.