Revert "Remove comments from .json because that's not allowed"

This reverts commit 6025384db0cdf6973a8d8ac43d5640cda69358fa.
Revert "Make browsersync an optional dependency, prevent installation from 'npm install'"

This reverts commit 7cfe78e0932640f22e8bbdcc5038d2318d7fbab3.
Thank you cache