This updates translate-tag.rb to parse all strings. This means that
we can add items such as {{ site.name }} into the source strings
and the plugin will do the rest. We no longer need hacky a
hacky workaround.
* Translate more of index.html, with translations sourced from
deepl.com
* Relax the plugin to allow capitalization, periods, exclamation
marks, and question marks in the Weblate ID for YAML src.
This helps differentiate between similar but different strings.
Adds in support for https://github.com/signalapp/jekyll-simple-i18n.
The plugin did not work with the github-pages gem, so github-pages was
switched with jekyll (which is what the current i18n branch does anyway).
