python-userpath: Add new package

The patches have been submitted upstream in
https://github.com/ofek/userpath/pull/52 and
https://github.com/ofek/userpath/pull/53.

From the README:

This is a tool for modifying a user's PATH.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

lang/python/python-userpath/test.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+[ "$1" = python3-userpath ] || exit 0
+
+userpath --version | grep -Fx "userpath, version $PKG_VERSION"