Finalize any-page comment changes

- If `blogs` isn't set in the config file, `blog` is treated as a blog, to
avoid breaking existing sites
- If it is, only sections listed are treated as blogs, possibly
excluding `blog`
- Differences include comments, but also hn/lobsters links, time to
read, and tags (possibly non-exhaustive)

layouts/partials/blog_single.html

@@ -95,8 +95,6 @@
                 data-isso-lang="{{ .Site.LanguageCode }}"
                 src="//{{ .Site.Params.issoHost }}/js/embed.min.js"
             ></script>
-            {{ else }}
-            this is where comments would go
             {{ end }}
         </div>
     </div>