The publish script should only drop the old version if a new version exists.

[markuszoeller]

See details in commit cc94644

The important lines are

markuszoeller.github.io/publish-gh-pages.sh

Lines 37 to 38 in cc94644

	rm -rf * # This is troublesome for custom domain names; add a CNAME file later
	cp -Rf ${HOME}/${temp_dir}/* .

Don't delete if there isn't something new!