[DO NOT MERGE UNTIL M7 RELEASED] XD-1622: Added the display of the batch step type to the UI

* Added code to pull step type out of the StepExecution's ExecutionContext.
* Added code to pass type to UI.
* Updated Spring Batch version to the current snapshot to use updates made in batch to support this feature.
Should we have either have:

* Tests that verify that all classnames are valid or
* Use classes directly to get classnames

Just want to make sure that when those classes change/get refactored, we know about it.