code: protected void beginStage(final String header, final String stage,
              final String numStages) {
          boolean print = getPhaseConfiguration().isVerbose();
          if (print) {
              StringBuilder bldr = new StringBuilder();
              bldr.append(INDENT);
              bldr.append("Stage ");
              bldr.append(stage);
              bldr.append(" of ");
              bldr.append(numStages);
              bldr.append(": ");
              bldr.append(header);
              reportable.output(bldr.toString());
          }
      }
docs: Sends {@code "=== <header> ==="} to {@link Reportable#output(String...)
  output}
  
  @param header Non-null header
  @param phase Non-null phase
  @param stage Non-null stage