link update

Author: nschloe

Makefile

@@ -8,9 +8,8 @@ tag:
 	@if [ "$(shell git rev-parse --abbrev-ref HEAD)" != "master" ]; then exit 1; fi
 	curl -H "Authorization: token `cat $(HOME)/.github-access-token`" -d '{"tag_name": "v$(VERSION)"}' https://api.github.com/repos/nschloe/tikzplotlib/releases
 
-upload:
+upload: clean
 	@if [ "$(shell git rev-parse --abbrev-ref HEAD)" != "master" ]; then exit 1; fi
-	rm -f dist/*
 	# https://stackoverflow.com/a/58756491/353337
 	python3 -m pep517.build --source --binary .
 	twine upload dist/*

README.md

@@ -23,7 +23,7 @@ figures like
 for native inclusion into LaTeX or ConTeXt documents.
 
 The output of tikzplotlib is in
-[PGFPlots](http://pgfplots.sourceforge.net/pgfplots.pdf), a TeX library that sits on
+[PGFPlots](https://github.com/pgf-tikz/pgfplots/), a TeX library that sits on
 top of [PGF/TikZ](https://en.wikipedia.org/wiki/PGF/TikZ) and describes graphs in terms
 of axes, data etc. Consequently, the output of tikzplotlib