[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.
Could possibly do an assertion using `StringUtils.hasText()` here to tighten things a bit.