Multilingual support

[pmviva]

I would like to propose implementing i18n support in this theme since Hugo has multilingual mode since a long time ago.

1. The theme should provide default English (and possibly Spanish, since is my native language) translation for all strings
2. Move all string translation from config.toml to its own i18n file, for example contact form field labels
3. The theme should display, in the main menu, links to the translated content of the current page
4. Make sure the theme is using absLangURL and relLangURL as per the Hugo documentation
5. The example site should be adapted in order to enable multilingual mode

If you are OK with this, I could implement the feature.

Best regards
Pablo

[Programazing]

@pmviva

I've forked this repo and started working on updating it if you're interested in an actively developed theme:

https://github.com/Programazing/hugo-strata-theme-II