Include event type in speakers.json

It doesn't seem like private information, and I'm using it for https://www.emfcamp.org/talks/
JSON for public events view.
fixes #140 directly in the query
Add scheduling info to events JSON view.
use hex based guid for events
Merge branch 'russss-public_events_view_improvements'
add event.guid to json, as it is stable
put new event json into static export too