Added r-tidyverse

This literally took 2 weeks. I can't believe it takes 2 weeks to package
the TidyVerse. What even is the state of R packaging.

Added missing LICENSE

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.