Fails to start with non-descriptive message if <formatter /> tag is missing from a logger.

The error message for a missing <formatter /> tag needs to be more descriptive. If a formatter is required, run a validation test. Otherwise perform null checks.

Example:
09:53:28,326 ERROR [org.jboss.msc.service.fail] MSC00001: Failed to start service jboss.logging.handler.CONSOLE: org.jboss.msc.service.StartException in service jboss.logging.handler.CONSOLE: Failed to start service
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1786)
at org.jboss.msc.service.ServiceControllerImpl$ClearTCCLTask.run(ServiceControllerImpl.java:2291)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [:1.6.0_26]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [:1.6.0_26]
at java.lang.Thread.run(Thread.java:662) [:1.6.0_26]
Caused by: java.lang.NullPointerException
at org.jboss.as.logging.ConsoleHandlerService.start(ConsoleHandlerService.java:55)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1765)
... 4 more