Add missing customizer comment
Merge pull request #13002 from ZDroid/hash

Add missing customizer comment
Bump Jekyll version used in Travis to v1.4.2.

Note that while v1.4.3 is the latest stable version, it has a nasty Windows bug.
(https://github.com/jekyll/jekyll/issues/1948)
Merge branch 'master' into modular-the-mixins
even more grunt