message: Another attempt to fix boost error in clang.
diff: @@ -113,7 +113,7 @@ namespace client {
  return;
  }
  // get the articulation spec for specified skeleton sensor
  - Json::Value articSpec = data.spec[m_sensor.value()];
  + Json::Value articSpec = data.spec[(*m_sensor)];
  // update articulationSpec of skeleton component
  Json::FastWriter fastWriter;
  std::string strSpec = fastWriter.write(articSpec);
  