Better UI workflow

[kaymckelly]

instead of starting by choosing the conference template, we should be able to import the event from the calendar of events, which will give us a better basis of starting the program

[kmccurley]

See how https://iacr.org/cryptodb/pc is built, where it queries the events database. We could also just use the conference table in cryptodb.

[kmccurley]

It turns out that there are many failure modes for our new workflow that we'll have to deal with.

1. what if the conference hasn't been listed in the calendar of events yet? We have seen people neglect this until quite late and just make up the meta.json file for their site.
2. I currently fetch the future events using this link and this gives us latitude, longitude, but it turns out that looking up the timezone from this is a little tricky (in part because the program could be made up at a time before a switch to daylight savings). I'm inclined to just guess based on the city and country instead, but even that will require a cloud API.
3. I'm no longer convinced that the forward/back buttons make sense.