Update gistBlogger.js path

The Problem
You've got a raw.github.com URL that points to some work-in-progress HTML, JavaScript, or CSS. You'd like to share it with someone for a quick demo, or maybe you'd like to use it in a jsPerf test.

Too bad! Most things served from raw.github.com have a text/plain content type and are served with an X-Content-Type-Options: nosniff header, which means HTML won't render, and some browsers won't execute JavaScript or apply CSS.