Merge branch 'master' into release-4.1

* master:
  Several configurations have been deprecated in current Jekyll. Re-run gem install jekyll.
  typo in pipeline doc
change the rest of instances of 4.1 -> to 5.0
links to other the documentation for previous versions on the Releases page
delete extra whitespace
skeletal release notes for 5.0
Merge branch 'release-4.1'

Conflicts:
	5.0/index.md
	_layouts/default.html
	index.html