Switching docs highlighting to highlight.js .. Docs build super fast again!

docs/content/extras/aliases.md

@@ -18,13 +18,12 @@ Luckily, this can be handled easily with aliases in Hugo.
 
 ## Example
 **content/posts/my-awesome-blog-post.md**
-{{% highlight yaml %}}
----
-aliases:
-    - /posts/my-original-url/
-    - /2010/even-earlier-url.html
----
-{{% /highlight %}}
+
+    ---
+    aliases:
+        - /posts/my-original-url/
+        - /2010/even-earlier-url.html
+    ---
 
 Now when you go to any of the aliases locations they
 will redirect to the page.