Update README.md

I thought that it would be handy to have a link to the working slideshow for those that don't know about Github pages. 

PS: You have a great presentation! Thank you for that.
Merge pull request #1 from theInternauts/patch-1

Update README.md
Update README.md
added google analytics (cause data)
Merge branch 'master' of github.com:vicapow/angular-d3-talk