There are some utility classes/services that were generic to YARN, and which are better off there now that we've iterated through using them
- ServiceLauncher entry point, exit codes and exceptions. This will need tests.
- workflow services: sequence, compound, event
- cleanup services (web, IPC, closeable). These should be templatized first.
If we get these into Hadoop 2.5 we can switch to the yarn-packaged successors to the internal implementations.