Remove course ID from title in course about page

Having the course ID as course title doesn’t make a lot of sense (SEO, user comprehension, etc.)
It’s also in contradiction with the `og:title` property.

As for the `<h1>` title, the course ID is redundant with the "Course number" in the sidebar right below it:

![screen shot 2014-06-20 at 3 38 36 pm](https://cloud.githubusercontent.com/assets/166147/3340678/5e44e384-f880-11e3-8238-d45fc6ee448f.png)