message: Print a message to stdout about paused/resumed
diff: @@ -2702,6 +2702,16 @@ void renderer::on_key_press(key_event const& event)
  case keyboard::Space:
  paused = !paused;
  +
  + if (paused)
  + {
  + std::cout << "Path tracer convergence paused\n";
  + }
  + else
  + {
  + std::cout << "Path tracer convergence resumed\n";
  + }
  +
  break;
  default:
  