#27, #30 - Added WorkoutSession as part of the underlying framework for
supporting workout goals.  This version runs successfully in Verifier
with the following exceptions:
1. When the workout timer is paused, the class-based state model for the
GPS continues ignoring a timeout event.  Probably this is caused by a
failure to unregister with the GPS when the workout timer is stopped.
2. When the workout timer is reset, the heart-rate samples are cleared,
but not the rest of data in the WorkoutSession such as currentSpeed,
currentPace, accumulatedDistance, and currentHeartRate.
#27, #30 - Added WorkoutSession as part of the underlying framework for
supporting workout goals.  See previous commit comment for details, as
it seems I failed to check the boxes for any of the files during the
previous commit operation.