Next, previous, and home links in articles

Currently not enabled, but have commented out sections for these, and
CSS to apply when they're ready.
New template for comments on posts
Set session_name to localhost if localhost()

Prevents circumstances where session would not work if 127.0.0.1. Still
susceptible if accessed by IP address.
Add optional confirmation to form submissions
Import function find_invalid_inputs()

Matches $_REQUEST to patterns by key. Returns first that doesn't match
pattern.
Do not show <details> if has nothing but <summary>
Add in comments feature!

Add comments form in a <dialog> to posts template.
AJAX handler in ajax.php to add comments to database and append
submitted
comments to post	.
Loop through an additional query for comments when loading posts.