Set the minimum update rate for master server host information update.
Normally host updates are only sent if something in the host information has changed (like connected players).
The update rate defines the minimum amount of time which may elapse between host updates. The default
value is 60 seconds minimum update rate (where a check is made for changes). So if one host update is sent and
then some field changes 10 seconds later then the update will possibly sent 50 seconds later (at the next change check).
If this is set to 0 then no updates are sent, only initial registration information.