fs 1.5.1

• Gábor Csárdi is now the maintainer.

• fs is now licensed as MIT (#301).

• dir_create() now restores the previous umask (#293)

• file_exists() is now much faster (#295)

• options(fs.fs_path.shorten) can now be used to control how paths are shortened in tibbles.
  The default value is "front", valid alternatives are "back", "middle" and "abbreviate". (#335)

• options(fs.use_tibble = FALSE) can now be used to disable use of tibbles (#295).

• path_tidy() now works with non-UTF8 encoded paths (@shrektan, #321).