New port: devel/py-pygitup

PyGitUp is a Python implementation of the great aanand/git-up/. It
not only fully covers the abilities of git-up and should be a drop-in
replacement, but also extends it slightly.

WWW: https://pypi.python.org/pypi/git-up

PR: 198666
Submitted by: Maxim Filimonov <che@bein.link>