Change how 'open' events are logged.
Now include default notebook opens
Make more info available to tracking services (still need to change
tracking services to consume it)
Fix and change tracking service about 'open' events logging
The code that determines notebook type was still using the logic from before the URL scheme change
Under current scheme, the notebook type has 2 parts: uriType and
notebook format. The tracking service now record the notebook format.
Issue #360 was logged to identify what exactly should be logged.
Add event logging for outputdisplay usage
Merge remote-tracking branch 'origin/master' into alee/metrics
Merge pull request #372 from twosigma/alee/metrics

Make Beaker able to log more to metrics