Merge all reference.conf files into one file in jar

Application only worked when run within Eclipse.  Outside eclipse running as a jar file only the first reference.conf files was found, rest ignored.  See http://doc.akka.io/docs/akka/snapshot/general/configuration.html#When_using_JarJar__OneJar__Assembly_or_any_jar-bundler for more information, but basically need the shade plugin to join all the reference.conf into one file instead.