TEZ-420. Change Map/Reduce Processor to work with the new engine APIs (bikas)
TEZ-442. Handle events generated by I/O initialize and close (part of
TEZ-398). (sseth)
TEZ-438. Allow users to configure a Partitioner in Tez-Engine
compoenents, which can be instantiated via reflection (part of TEZ-398).
(sseth)
TEZ-441. Move tez event handling thread into the LogicalTask from YarnTezDagChild. (hitesh)