Add Message Broker calls to user events.

# Changes
 - Adds Message Broker calls to user events.

@DeeZone Can you look at the payloads, and tell me if anything is missing or should be changed?
Added in 27a8278. We can have Voting App determine if user is in affiliate country for now, but eventually there should be a canonical source for that information (rather than hardcoding it in each individual app.)