message: gltfpack: Fix bufferspec overflow on large files
  On large files 32 characters aren't enough to encode the buffer size...
diff: @@ -2355,7 +2355,7 @@ int main(int argc, char** argv)
  return 4;
  }
  - char bufferspec[32];
  + char bufferspec[64];
  sprintf(bufferspec, "{\"buffers\":[{\"byteLength\":%zu}],", bin.size());
  json.insert(0, bufferspec);
  