doc improvement
Fixed an intermittent dead lock problem.

... which was made likely because callback to GraphListener was happening from a thread that owned various locks.

In this change, I'm queueing up all the notifications until we get to the end of the CPS program executing thread,
then firing off all the notifications at once.

Reference: https://trello.com/c/7aTFYWM5/26-intermittent-deadlock
Weakening the assertions.

Now I'm seeing the output like this:

    Started
    Trying!
    Trying!
    Trying!
    Done!
    Over!
    Running: Retry the body up to N times : Start
    Running: Retry the body up to N times : start body : Start
    Running: Retry the body up to N times : start body : End
    Running: Retry the body up to N times : start body : Start
    Running: Retry the body up to N times : start body : End
    Running: Retry the body up to N times : start body : Start
    Running: Retry the body up to N times : start body : End
    Running: Retry the body up to N times : End
    Running: End of Workflow
    Finished: SUCCESS

So for the time being relaxing the ordering assertion.
Merge commit 'd43c4aee68fec9b88491063127e84af28a5d6ef2'