docs: public void load() throws IOException {
          logRecorders.clear();
          File dir = configDir();
          File[] files = dir.listFiles((FileFilter)new WildcardFileFilter("*.xml"));
          if(files==null)     return;
          for (File child : files) {
              String name = child.getName();
              name = name.substring(0,name.length()-4);   // cut off ".xml"
              LogRecorder lr = new LogRecorder(name);
              lr.load();
              logRecorders.put(name,lr);
          }
      }