message: gltfpack: Refactor basisu detection
  Now that basisu supports -version command we can simply call it with
  that to detect the executable.
diff: #include <stdlib.h>
  #include <string.h>
  -#ifdef _WIN32
  -#define popen _popen
  -#define pclose _pclose
  -#endif
  -
  static const char* kMimeTypes[][2] = {
  {"image/jpeg", ".jpg"},
  {"image/jpeg", ".jpeg"},
  @@ -74,28 +69,20 @@ static const char* mimeExtension(const char* mime_type)
  bool checkBasis()
  {
  -#ifdef __EMSCRIPTEN__
  - return false;
  -#else
  const char* basisu_path = getenv("BASISU_PATH");
  std::string cmd = basisu_path ? basisu_path : "basisu";
  + cmd += " -version";
  +
  #ifdef _WIN32
  - cmd += " 2>nul";
  + cmd += " >nul 2>nul";
  #else
  - cmd += " 2>/dev/null";
  + cmd += " >/dev/null 2>/dev/null";
  #endif
  - FILE* pipe = popen(cmd.c_str(), "r");
  - if (!pipe)
  - return false;
  -
  - char buf[15];
  - size_t read = fread(buf, 1, sizeof(buf), pipe);
  - pclose(pipe);
  + int rc = system(cmd.c_str());
  - return read == sizeof(buf) && memcmp(buf, "Basis Universal", sizeof(buf)) == 0;
  -#endif
  + return rc == 0;
  }
  bool encodeBasis(const std::string& data, const char* mime_type, std::string& result, bool normal_map, bool srgb, int quality, bool uastc)
  