code: func NewFSSyncProvider(dirs []SyncedDir) session.Attachable {
  	p := &fsSyncProvider{
  		dirs: map[string]SyncedDir{},
  	}
  	for _, d := range dirs {
  		p.dirs[d.Name] = d
  	}
  	return p
  }
docs: // NewFSSyncProvider creates a new provider for sending files from client