Translate README.md

If you speak another language, I would appreciate your help in translating the README.md.

For tables, checklists, or other data that might change, please indicate that that information is in the main README. Otherwise every change to the main README will need to be replicated to the other READMEs.

^ I've tried to do this a bit in the French README. The only thing you need to replicate when adding a new language is the line that lists all the languages.

Thank you!