Some notes on the Best practice article

[maelle]

i.e. https://docs.ropensci.org/crul/articles/best-practices-api-packages.html

• It lacks an intro.

• Could it mention retry?

• Also, from that article I'd link to the same article in httr because some concepts will apply to packages wrapping crul.

• For vcr add a link to the http testing book too?

[sckott]

thanks @maelle all sound good, will do