fix typo in <h2> tag of _posts/2012-03-09-simple-html5-explanation.md post
fix typo in <h2> tag of _posts/2012-03-09-simple-html5-explanation.md post

kaidez/kaidez.com,kaidez/kaidez.com,kaidez/kaidez.com,kaidez/kaidez.com