private void logOrThrow(String message) {
        if (skipUpgradeCheck)
            log.log(WARNING, message);
        else
            throw new RuntimeException(message);
    }
Contains version information for this configserver. Stored both in file system and in ZooKeeper (uses
data in ZooKeeper if distributeApplicationPackage and data found in ZooKeeper)

@author Ulf Lilleengen
@author hmusum
configserver/src/main/java/com/yahoo/vespa/config/server/version/VersionState.java