WIP: Readability and style updates

This is a collection of partial fixes for 1206641 and some of 1210645 as well as the two overlap in many cases.  The end goal is to make our site/core manifests more self-documenting and easier for users to read and understand.  I'll leave this open for a few days so folks can review and add additional cleanups to the topic branch, then we'll squash merge it later in the week.  The commits I've already added below clarify language and provide a slew of puppet-lintish fixes that make the code easier to grock.