Fix typo in comment.
Delete harmless but unnecessary space in pygmentize cmd line
Index pages should show links for ALL posts. Closes #31.

Even for posts beyond max-index-items setting. For those, show only
the title and date/tags.

Also: Tweak the post title, date, and tags HTML to:
- All be inside an HTML5 <header> semantic element.
- Use a "date-and-tags" class for the <p> element.