Update to latest pathlib_abc

[justindujardin]

Opening an issue to track that we're out of date with the latest pathlib_abc. This isn't a worry per se, but we'd like to stay updated to get improvements.

From: #105 (comment)

FYI, I've published pathlib-abc 0.2.0. Changelog: https://pathlib-abc.readthedocs.io/en/latest/changes.html

[barneygale]

pathlib-abc should stabilise quite quickly. The changes from 0.1 to 0.2 will be the most drastic of any version bump I suspect. I'm hoping to put out a 1.0 release mid-year.