Add JSON-based API to grab filtered lists of events
Adds a JSON-based API. Either pass in base_url/api/rest_of_url or url?format=json to get the JSON results.
Also as part of this, main.py got a bit unwieldy so I factored out/consolidated a lot of the web code to web.utils and web.templates.
Implements and closes #16 (closed).
Edited by Patrick Godwin