Fixed typos and updated broken bootstrap.min.css link

I have fixed some typos/grammar and improved the language to make it read better in places.

The link to the Bootstrap stylesheet was outdated and no longer working, so I updated it to http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/css/bootstrap.min.css (the most recent version while Bootstrap 3 is still a work in progress).

Thanks :)