OTS — child lifetime

In order to implement the ChildLifetime SignalSet correctly we actually need two separate SignalSets (ChildLifetimeBegin, ChildLifetimeComplete), one for each of the two Signals. In addition, it is necessary that the activity is still active on the thread when childComplete is generated, in order that the actual activity identity can be encoded in the Signal. So, we need to reverse the order of the Synchronization and ChildLifetime SignalSets.

see above