code: func (b *Box) AddBytes(path string, t []byte) error {
  	m := map[string]file.File{}
  	f, err := file.NewFile(path, t)
  	if err != nil {
  		return err
  	}
  	m[resolver.Key(path)] = f
  	res := resolver.NewInMemory(m)
  	b.SetResolver(path, res)
  	return nil
  }
docs: // AddBytes sets t in b.data by the given path