we don't need to bother with transifex, i think. there are very few strings to translate. I can just send it to the riseup translation group (translators@lists.riseup.net), once we nail down the strings we want for now.
I'm playing around with https://godoc.org/golang.org/x/text it's the official implementation from the golang team to do localization. It might be a better fit than go-i18n.
It looks like golang.org/x/text is the future of localization of applications in go, it is currently under development and a bit rough in the edges. But I kind of like it more than go-i18n. I got something promising there, I'll make a MR and see what others think about it.