CSP: Porting from Respec to Bikeshed.

Bikeshed gives us much better ability to interlink with other
specifications, and cleaner code across the board. It also means we can
easily steal the CSSWG's stylesheet, which is a significant improvement
over what we've been using.
Merge pull request #19 from w3c/bikeshed

CSP: Porting from Respec to Bikeshed.
CSP: Updating with the new URL.