Inital translations

[cherta]

I tried hard not to add literal translations but to communicate the idea, maybe now the English version is a bit out of sync since the concept of the site has shifted since I first wrote the english pages. We may need to revisit the english pages as well.

The work is pretty straightforward, hugo enables translations by prefixing the language name to the file extensions. For example contents/index.md can be translated to spanish by creating a new file named contents/index.es.md.

There is still somre repeated code on the index page since it's not only content but some styles and the newsletter form, I think for now this works but if we find ourselves changing a lot the index page then we should move these resources to a more generic place.

[cherta]

Bueno, metí varios si no todos los comments que estaban mjy buenos. Estaría bueno darle otra vichada igual y dejarlo abierto algunos días más para que alguien más se sume.

[xymbol]

@cherta Dale, prometo una leída de punta a punta y/o pull-request.

[cherta]

@maurocarrero creo que ahí fueron las correciones que pasaste, estaban todas re bien!