Currently the theme generate gallery by listing image files in /content/imgaes. I think it would be useful if it's possible to include images hosted on external source, since many folks host sites on Github while Github is not ideal for hosting a large number of big image files. The way of inclusion could be - as I can come up with - putting image urls in a certain format in the gallery's index.md, or a single file containing list of urls in /content/imgaes.