Canceling execution does not work on Windows

[szeiger]

When you cancel a benchmark job with Ctrl-C, sbt prints the usual [warn] Canceling execution... message and then drops back into interactive mode, but the actual benchmarking process that was spawned by jmh is still running and keeps writing logs to the console. Pressing Ctrl-C again terminates sbt and disconnects the console from the process so the log output stops but jmh's java process is still running in the background. You have to kill it manually in task manager.