Send setup survey responses to the server

The setup survey presentation & submission logic had gotten disconnected. This hooks them up again so that setup survey responses are actually sent to the server.

Incidentally, as part of that:
* Now setting participant IDs
* Discovered that CHECKBOX questions were missing a name value; added that.
Hmm. I see what you mean, but the suggested code doesn't quite work. setupState() also calls setNewParticipantId. Also the local storage value has to be set somewhere so that it survives a Chrome restart; setting cesp.participantId = participantId isn't sufficient, we also need to propagate the new value to local storage. It seems to me like either way you're going to end up needing two methods, unless I'm missing something?