User.prototype.refreshAccount was responsible for multiple race
condition bugs as well as inefficient duplication of DB queries in an
attempt to correct such race conditions.
It has now been replaced by a more reasonable model:
* Global user account information and aliases are fetched in parallel
on socket connection
* Channel rank is fetched when the user tries to join a channel
Really the entire "Account" thing needs to be refactored/deleted and
replaced with separate global account and per-channel state, which I
plan to do, but this brings some minor benefit in the meantime
