TODO/bugs In SILC Server
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+ o After backup resuming protocol some of the server's SilcIDListData
+ on primary that came back online are NULL. Seems actually that the
+ udpate_client_by_server does not work since the client->router, and
+ the client->router->connection->user_data are not same, and they
+ should be.
+
o Server signoff notifys does not go to normal servers from routers.
o Channel user mode changes are notified unnecessarely when switching