code: public static void unregister(final JobID id) throws IOException {
  
  		final LibraryCacheManager lib = get();
  		lib.unregisterInternal(id);
  	}
docs: Unregisters a job ID and releases the resources associated with it.
  
  @param id
  the job ID to unregister
  @throws IOException
  thrown if the library cache manager could not be instantiated