Recent changes to APE were sub-optimal because the subclasses
had to call back into the parent abstract class.
Deprecate doPoll() on APE.
Introduce a temporary intermediate abstract class that supports
transaction synchronization.
This class will be deprecated in 3.0.0 when its methods will
be pulled up into APE.
INT-2815 Polishing
Make ATSPE package visibility.
Add helpers to enable early migration to 3.0 structure.
INT-2815 Polishing
Fix javadoc to emphasize that doPoll() will no longer
be overridable in 3.0.
Rename doReceive() to receiveMessage() to match more closely
with handleMessage().
INT-2815 Polishing
Fix message in UnsupportedOperationException.
6f4800a904