[fr] Updating internationalization-and-localization.rst

Mise à jour de Language Files & Setting the Default Locale
Une idée pour la traduction de Runtime ?
Update internationalization-and-localization.rst
[fr] internationalization-and-localization.rst

Correction d'un terme
Merge pull request #2121 from bracketouverte/patch-3

[fr] Updating internationalization-and-localization.rst