message: basic command line parsing for ospExamples
diff: using namespace ospray;
  static std::string rendererType = "pathtracer";
  +static std::string builderType = "boxes";
  int main(int argc, const char *argv[])
  {
  initializeOSPRay(argc, argv);
  + for (int i = 1; i < argc; ++i) {
  + std::string arg = argv[i];
  + if (arg == "-r" || arg == "--renderer")
  + rendererType = argv[++i];
  + if (arg == "-s" || arg == "--scene")
  + builderType = argv[++i];
  + }
  +
  {
  - // auto builder = testing::newBuilder("gravity_spheres_volume");
  - // auto builder = testing::newBuilder("random_spheres");
  - // auto builder = testing::newBuilder("cornell_box");
  - // auto builder = testing::newBuilder("boxes");
  - // auto builder = testing::newBuilder("curves");
  - // auto builder = testing::newBuilder("streamlines");
  - // auto builder = testing::newBuilder("cylinders");
  - // auto builder = testing::newBuilder("subdivision_cube");
  - auto builder = testing::newBuilder("unstructured_volume");
  + auto builder = testing::newBuilder(builderType);
  testing::setParam(builder, "rendererType", rendererType);
  testing::commit(builder);
  