devel/py-fs: update to 0.5.4

0.5:

• Ported to Python 3.X
• Added a DeleteRootError to exceptions thrown when trying to delete '/'
• Added a remove_all function to utils
• Added sqlitefs to fs.contrib, contributed by Nitin Bhide
• Added archivefs to fs.contrib, contributed by btimby
• Added some polish to fstree command and unicode box lines rather than ascii art

PR: 204579
Submitted by: douglas@douglasthrift.net (maintainer)