public void registerLogHandler(LogHandler lh, String threadName) {
        HandlerThread ht = getHandlerThread(threadName);
        ht.registerHandler(lh);
        threadNameForHandler.put(lh, threadName);
    }
This class implements the log server itself.  At present there is
no runtime configuration;  the server starts up, binds port 19081
and loads builtin plugins.

@author Bjorn Borud
@author Stig Bakken
logserver/src/main/java/com/yahoo/logserver/Server.java