Image styling and fix pygments issue

This commit includes changes to display images more cleanly, centered
within the post. Also, the pygments styling wasn't working at all
because the parent element class was incorrect. The pygments styles have
also been tweaked to improve their presentation.
Remove syntax highlighting from old posts

Some old posts were triggered syntax auto-detection when in fact the
text should have been presented as plaintext.
Fix create-post.py to set post time correctly

Previously the `create-post.py` script would only set the date
correctly, the time was always midnight. This commit fixes it.
Added two most recent posts, including images
Merge commit '33b3b4288b338a0766a576038c17fd2de4f765b2'