code: public QueueReference build(Map<String, String> params, boolean crumbFlag) throws IOException {
          return build(params,null,crumbFlag);
      }
docs: Trigger a parameterized build with string parameters only
  
  @param params the job parameters
  @param crumbFlag true or false.
  @return {@link QueueReference} for further analysis of the queued build.
  @throws IOException in case of an error.