DOC-1281 Puppet Server puppet_conf_setting_diffs edit

Edited puppet_conf_setting_diffs.markdown
DOC-1281: Edits to puppet_conf_setting_diffs.

Title change, fixed style on file names (`puppet.conf` -> puppet.conf), and fixed awkward usage error.
Merge pull request #315 from jbondpdx/conf-setting-diff

DOC-1281 Puppet Server puppet_conf_setting_diffs edit
(docs) Add Jekyll's yaml frontmatter to all docs pages

This will let us display Puppet Server docs on the main website.
(docs) Adjust wording of logging config section
(docs) Fix glitchy markdown and a few broken links

Putting a space between link text and the link URL only works in a few Markdown
implementations. The one our docs site uses can't handle it. :/
(docs) Point to both foss and PE conf.d paths
(docs) Finalized service page for a Puppet Server master

This page is a counterpart to the service information pages about the rack and
webrick masters. It will be displayed alongside them in the Puppet docs.
(docs) Fix glitchy or difficult Markdown formatting

Github's markdown will accept triple-backticks as code block delimiters,
but triple-tildes are more widely compatible. (Currently, the renderer
our docs site uses can't handle the triple-ticks.) This also cleans up
some nested lists to the least common denominator.
(docs) Mark linked setting names as code in puppet_conf_setting_diffs.markdown