Change "what jQuery does for you" link into a github repo

@rwaldron @jdalton @paulirish

May I suggest that we host your list of bugs on Github? Using Google Docs makes it more difficult for others to add to and improve it. I've created a new repo called "whatjquerydoesforyou" to demonstrate what I mean,  and I've ported the content from the original note into Markdown format:

https://github.com/gregsabo/whatjquerydoesforyou/blob/master/README.md

If you like, feel free to move the README into a repo of your own since it's all your content.