Fix live examples link

Hotlinking to raw.github.com (or raw.githubusercontent.com) no longer
works in major browsers since they started [respecting Github's use of
the `X-Content-Type-Options: nosniff`](https://github.com/blog/1482-).

RawGit to the rescue.
Merge pull request #437 from evanrmurphy/fix-live-examples-link

Fix live examples link