Added thumbs.db to .gitignore.
Added Flattr button.

Also moved it and the PayPal button to the right side of the page.
Merge branch 'pixyll-social-buttons'
Added donation visibility post.
Added Flattr donations post.
_config.yml update.

Let GitHub use its default syntax highlighter (pygments), and enable
usage of @mentions and emoji.
Added Javascript HTTPS redirect.

Not ideal, but better than nothing.
Merge branch 'content'