Add a System.LoggerFinder for Java 9+

In Java 9 a java.lang.System.Logger and java.lang.System.LoggerFinder were added for system logging. By default this uses JUL. However as this is designed for system level logging there is a chance that the LogManager could be activated before the java.util.logging.manager system property is set. Creating a java.lang.System.LoggerFinder which sets the property will allow the JBoss Log Manager to be used assuming it's on the class path.