Small update

I just did a couple of small updates, finally!

• MathJax is working properly again (although the firefox bug regarding mathbf-fonts persists…)
• I finally changed my license to cc-nc-sa 3.0-licencsing as can be seen by the footer.
• The css is now valid although the html is still a mess (e.g., the cutting of the posts on the front page often leads to missing closing tags).

Ah well, you can’t have everything…