Tidy up doc pages a bit (#1888)

* Link code tabs

* Overviews for sections

* Reorder features

Author: Goooler

mkdocs.yml

@@ -31,9 +31,11 @@ theme:
     text: 'Lato'
     code: 'JetBrains Mono'
   features:
+    - content.action.edit
     - content.code.copy
     - content.code.select
-    - content.action.edit
+    - content.tabs.link
+    - toc.integrate
 
 markdown_extensions:
   - smarty