`PathRI` behavior incorrect/not helpful on Windows

[mih]

Demo:

>>> pathlib.PureWindowsPath("C:\\Windows").as_uri()
'file:///C:/Windows'

>>> RI("file:///c:/Windows").localpath
'/c:/Windows'

>>> pathlib.PureWindowsPath('/c:/Windows')
PureWindowsPath('/c:/Windows')

Ergo, it get's transformed into an unusable string.

A better approach would be:

>>> nturl2path.url2pathname(urlparse("file:///c:/Windows").path)
'C:\\Windows'

nturl2path.url2pathname is called by urllib.request.url2pathname on windows.

[yarikoptic-gitmate]

Issue fixed in 0.17.10