Clean up CSS

- Add vim folds to make organized sections
- Rename a lot of classes from post- to page-
- Generalize series CSS classes better
- Clean up navbar div structure
- Remove langpicker and most of multilingual support
- many other minor tweaks

layouts/_default/baseof.html

@@ -10,9 +10,7 @@
 
         <a id="top" name="top" aria-hidden="true"></a>
 
-        <div class="top">
-            {{ partial "top.html" . }}
-        </div>
+        {{ partial "top.html" . }}
 
         {{ if not .IsHome }}
             {{ partial "breadcrumb.html" . }}