Log Message:
(archivers/R-zip) Updated 2.0.4 to 2.1.1
# 2.1.1

This version has no user visible changes.

# 2.1.0

* `unzip_process()` now does not fail randomly on Windows (#60).

* Now all functions handle Unicode paths correctly, on Windows
  as well (#42, #53).

* `unzip_process()` now works when R library is on different drive
  than `exdir` on Windows (#45)

* zip functions now have a `mode` argument to choose how files and
  directories are assembled into the archive. See the docs for
  details.

* zip functions now have a `root` argument, zip changes the working
  directory to this before creating the archive, so all files are
  relative to `root`.

* `zip()` and `zip_append()` are not deprecated any more, as it was
  hard to achieve the same functionality with the other zip functions.