Remove unsupported Java 9 options

Current Situation

• When starting the JobScheduler Master then a number of Java options are automatically added.
  • This includes the options: [-Xfuture] [-XX:+UseAltSigs] [-Xrs] [vfprintf]
  • A full example from the ./logs/scheduler.log files shows

    08 17:59:23.351 scheduler   15  4304.16C0 96.102MB Java options: [-Dlog4j.configuration=file:///C:/Program Files/sos-berlin.com/jobscheduler/jobscheduler-1.12.9/lib/log4j.properties] [-Djavax.xml.transform.TransformerFactory=net.sf.saxon.TransformerFactoryImpl] [-Xfuture] [-XX:+UseAltSigs] [-Xrs] [vfprintf] [-Djava.class.path=...
    

• The option UseAltSigs has been removed since Java 9. Therefore the following error message is written to stderr and is visible from the job log:

  OpenJDK 64-Bit Server VM warning: Ignoring option UseAltSigs; support was removed in 9.0

Desired Behavior

• The Master should not add the UseAltSigs Java option. At least not when used with Java releases starting from Java 9.