Allow property injection into any artifact rather than just JSR interface impls.

* Remove isBatchArtifact check
* Reduce BatchArtifact.BatchArtifactType into BatchArtifactType
* Import JSR JSL definition from Spring config loaded by JsrJobOperator, update test
  for property injection into Tasklet and cleanup pre-parsing checks
Added wait in JsrJobOperatorTests#testApplicationContextClosingAfterJobSuccessful to give application context a chance to shut down before re-running the job
cleanup
BATCH-2188: Refactored package.html to package-info.java and added package-info.java to all packages that needed one
add ClassifierCompositeItemProcessor
BATCH-2195: Document Spring Batch Integration

* Removed APT files
* General formatting and spelling fixes
* Converted README.md to docbook
* Expanded converted README.md docs to include usable code snippets