Log Message:
(devel/R-fs) Updated 1.5.2 to 1.6.2

# fs 1.6.2

* `path_ext_set()` can now handle extensions that contain a `.`,
  e.g. `csv.gz` (@mgirlich, #415).

# fs 1.6.1

No user visible changes.

# fs 1.6.0

* inputs to `path_real()` and `path_join()` are coerced to character
  for consistency with other functions (@raymondben, #370)

* fs uses libuv 1.44.2 now.