get prepared for "reflective access denied" in future java releases

[gmuth]

This warning does currently not break operation but should be looked after anyway:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.xbill.DNS.ResolverConfig
(file:.m2/repository/dnsjava/dnsjava/2.1.6/dnsjava-2.1.6.jar) to method sun.net.dns.ResolverConfiguration.open()
WARNING: Please consider reporting this to the maintainers of org.xbill.DNS.ResolverConfig
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

[stodge]

MulticastDNSJavaNameServiceDescriptor fails to compile now as sun.net.spi.nameservice.NameService and sun.net.spi.nameservice.NameServiceDescriptor no longer exist in the JDK.