Can be always enabled
* TaskState.java: Handle .processPerformTerminating in startRunning, and zombied states. Do not pass the terminating exit status to Task .sendContinue. * LinuxTask.java: Always enable exit tracing. * Task.java: Delete .traceExit. * Task.java: Merge .performExited into .performTerminated. Replace .performExiting into .performTerminating. * LinuxHost.java: Update. * TaskState.java: Replace .processPerformExiting with .processPerformTerminating. Merge .processPerformExited into .processPerformTerminated. * TestLib.java, LinuxHost.java: Update Wait .Observer objects so that .eventExit has additional signal, and coreDumped parameters, and .exited is merged into .terminated. * TaskObserver.java: Replace .Exiting with .Terminating; Merge .Exited into .Terminated.