[FR] Fix some errors in example codes + fix 1 translation

[Olyno]

I replaced every 'voici un test d''après moi' with "voici un test d'après moi" (just an example sentence).
I fixed a translation too.
Everything about French's transltation.

[forresst]

You're right, but all AVA examples use the simple quote, so to maintain consistency in the examples, it would be better to do this:

test.serial.todo('penser à l\'écrire plus tard');

Can you change in this way?

[forresst]

Thank you very much for your help