~dricottone/pkgbuilds

ref: 5c473508665c0852889f1183af26bc1390f631bc pkgbuilds/r-magrittr d---------
Added r-stringr
Initial commit

A long journey to packaging r-tidyverse. The current highest-level
packages that are successfully built are dtplyr, waldo, callr, and xml2.
A handful of others (brio, digest, praise, units, zeallot) are currently
freestanding but will become dependencies soon.