Change header to my own logo.
Increase the width of the website, it was too narrow for my tastes.

The new width still allows it to fit in half of a 1600x900 screen.
Remove "till next time" signature.
Adjust position of the navigation arrows as we increased the width of the
content in a previous commit.
The scribble in the signoff looks better centered.
Remove css for iframes, it screws up youtube embedding.
Add lightbox plugin for viewing images.
Add MathJax for LaTeX.
Hide default sample posts.
Enable disqus comments in pages too.
Add all the stuff ported from wordpress.