Solve md on sphinx project problem

[dpshelio]

The carpentries handbook uses sphinx but with md instead of rst pages. This produces that the links are lost during the translation phase. This has been noted upstream on carpentries/docs.carpentries.org#506
Possible solutions:

• Upstreams addopts rst as the format for all their pages
• we use pandoc to convert them before producing the translations tokens. This could work, but the then it may need to be converted back to md for the internal links (table of contents and within text) to work as the filenames may have changed.

[astrojuanlu]

Third option:

• Make Markdown links i18n-friendly

I would love to explore if this is at all possible, and try to go this route first :)