This is to achieve a clean separation of concerns - the watchdog is an inappropriate place for work management.
Also adds a WorkManager.RunInThreadPool() class which feeds through to Util.FireAndForget.
Also switches around the name and obj arguments to the new RunInThread() and RunJob() methods so that the callback obj comes after the callback as seen in the SDK and elsewhere
The functionality is the same but this allow us to monitor such tasks via "show threads" and abort them for test purposes, etc.
Also extends thread names to provide more info (e.g. SendInitialDataToClient says what client the task is for).
The major departure from flotsam is to send only one message per destination region, as opposed to one message per group member. This reduces messaging considerably in large groups that have clusters of members in certain regions.
Justin Clark-Casey (justincc)