UC-138 Update the user_fbconnect table and code that accesses it

Changes to record all the data necessary to disambiguate Facebook users now that we don't get a universally unique ID.

https://wikia-inc.atlassian.net/browse/UC-138
Do we need this to return a boolean? It looks like in the places where it's called it's not looking for a return value. The purpose of this method also seems like we could get by without.