Keeping FilePathsBase.jl in sync with Base.Filesystem

[rofinn]

I'm not sure how this would work, but it'd be nice if there was some way we could ensure that the FilePathsBase API is remaining in sync with Base.Filesystem. Currently, I'm reliant on folks letting me know when something isn't supported on newer releases.

[o314]

Hi there. Do you know that since python 3.6, a PurePath class and its two spec for posix and windows have been added to python stdlib https://docs.python.org/3/library/pathlib.html#pure-paths

There is an easy answer for julia now : do lobby enough to catch up with the same support level from julia lang and move FilePathsBase to Base.FilePaths o: