Added the implementation of a post processor to lazily init partition
related artifacts
* Added BeanFactoryPostProcessor
* Fixed StepContext creation (now creates one per thread)
* Fixed StepContext exit status processing (now keeps track of being set
 manualy or not
* Created new Flow implementation to handle JSR-352 state transitions
* Updated flow parsing to not default to completed if no other
 transitions are provided
Updated per code review