Small FR localisation enhancements (#3033)

* Small localisation enhancement.

Be consistent regarding "e-mail" vs "courriel": I suggest
using "courriel" to refer to the electronic message and
"e-mail" when used in "adresse e-mail".  This reflects
the usage I generally observe, but I may be wrong.

* Localisation enhancements.

Omit some commas: "..., ..., ou ..." should be "..., ... ou ..."
since "ou" already articulates the sentence.

Also replace "demande" by "requête" when it makes sense.