Social tracking

This PR tides up our social tracking by:
- adding new omniture props (requested from by Matt Koppka and Cantlin) to every social tracking event.
- change the body of our tweets to include the shortUrl instead of the full
- Add correct campaign tracking code to end of Twitter url

This should bring our social tracking more inline with R2's

/cc @gklopper @rich-nguyen @tackley 
(p.s. I will ship from home this afternoon)