WFCORE-194 Improve Debian/Ubuntu init.d shutdown process

The init.d script for Debian/Ubuntu can be improved in the way it shutdown the server...

If some process hang up, the actual script don't handle that scenario.

I think it's best to remove the loop completely and leave it as before (just the  $0 start)...

I was making more tests and start-stop-daemon takes care for the stop of the process with the --retry option... if there were some problemas preventing shutdown in the timeout it kills the process.