via Jetty IPAccessHandler to allow only configured IP's to access.
Handler is only loaded if a restriction is configured.
Since IPAcessHandler (Jetty 8) does not support IPv6 system property java.net.preferIPv4Stack=true
Testing showed system.setProperty seems to be sensitive to point of calling (earliest possible time seems to be best = early in yacy.main).
Moved the "isrunning..." just open browser check also to the new routine to preread the yacy.config only once.
reger