Remove headers. Fix casing. Add URL to category page.

content/posts/_index.md

@@ -4,6 +4,4 @@ title: "All Posts"
 subtitle: "Chronologically posted articles."
 ---
 
-# All Posts
-
-Articles are posted below in chronological order, and are also [available by tag here](/tags).
+Articles are posted below in chronological order. They may also be viewed by [individual tag](/tags) or [category group](/categories).