keenio: begin update to 3.0 for #327

/cc @calvinfo @ianstormtaylor @yields starting to update this one, we just need to wait for the fix so the module can load without AMD and it should be pretty much good to go!
@lancejpollard  I believe this should be //d26b395fwzu5fz.cloudfront.net/3.0.6/keen-tracker.min.js - no?  The full Keen library also pulls in Google Charts on load which is > 600kb