* Replace old `account`.`online` field by `account`.`active_realm_id`.
It have 0 if account offline.
NOTE: this break all scripts that use `online` field for seelct online characters, and it required update.
But from other side this reolve
* Bug with reset online state active realm at restart another realm.
* Let easy select online accounts for some specific realm if need.
Signed-off-by: VladimirMangos <vladimir@getmangos.com>
