code: public void register(FileSubscriber fileSubscriber, Identification identification) throws IllegalIDException {
          defaultFileSubscribers.add(fileSubscriber, identification);
      }
docs: Registers a {@link FileSubscriber} so that whenever any file is reloaded, the fileSubscriber is notified.
  
  @param fileSubscriber the fileSubscriber that should be notified when the reloadable file is reloaded
  @param identification the Identification of the FileSubscriber
  @throws IllegalIDException not yet implemented