Better logging in PresenceService, to help diagnose presence problems.
Removed an attempt to set a user's presence to "Region 0" when they HG teleport to another grid.

a) This shouldn't have been done because at that point the user is still logged-in to the current grid. b) It's not necessary because the user will soon be logged-out completely. c) And it didn't even work because the MySQL database layer prevents setting the region to 0.
Better error handling when retrieving offline IMs
Fixed: when a user logged-in, sometimes he didn't get notified of the Online status of friends, so they continued to appear Offline.

This happened because these notifications (the UDP packets) can only be sent to Root Agents. But the notifications were done in OnClientLogin(), at which point the client is still a Child Agent. Since a FireAndForget is used, it became a race condition as to whether the packets would be sent before or after the client became a Root Agent.

To fix this, we now only send the notifications once the client becomes a Root Agent for the first time.