Stable API should provide Agenda.getActivations()

The stable API lets you retrieve Agenda from WorkingMemory, and there is an IF for Activation. There should be a
List<Activation> getActivations
in the "stable" Agenda.

This would be highly useful for writing supportive code for inspecting the engine's state at critical points. (I don't see that restricting Agenda views to specific "groups" would be a benefit for such tasks.)