code: func genAll() ([]string, error) {
  	zipSource()
  	for _, platform := range []string{"linux", "darwin", "windows"} {
  		genBinaries(platform)
  		packBinaries(platform)
  	}
  	getVersions()
  	return []string{
  		"perkeep-darwin.tar.gz",
  		"perkeep-linux.tar.gz",
  		"perkeep-src.zip",
  		"perkeep-windows.zip",
  	}, nil
  }
docs: // genAll creates all the zips and tarballs, and returns their filenames.