SLIDER-94: moving the workflow services into their own package and give the names planned for YARN; review and clean up ServiceLauncher (which now uses SLF4J(
Merge branch 'develop' into feature/SLIDER-94-workflow-services-to-YARN
SLIDER-94: workflow and process execution service preparation -including moving tests to java 
SLIDER-94: workflow composite tests to java
SLIDER-94: workflow tests with common base -and all passing
SLIDER-94 purge obsolete groovy tests -now that they've been migrated to java
SLIDER-94 set thread name in workflow tests
SLIDER-94 more workflow tests and javadocs; sequence service now correctly terminates if started without any child services
Merge branch 'feature/SLIDER-94-workflow-services-to-YARN' into develop
Merge branch 'develop' of https://git-wip-us.apache.org/repos/asf/incubator-slider into develop
SLIDER-84 switch from thread-based container launch to executors