Gender aliases for user namespaces in French and Cajun French

NS_USER:
* User identifies as male: Utilisateur
* User identifies as female: Utilisatrice

NS_USER_TALK:
* User identifies as male: Discussion utilisateur
* User identifies as female: Discussion utilisatrice

Languages with fallback to French:
* applies to frc (Cajun French). This language also uses « Utilisateur »
  and « Utilisatric » to translate “user”.
* doesn't apply to bm, ff, frp, ht, ln, mg, pcd, sg, ty, wa, wo.

This change is a follow-up of I5825f750a58dd196f907ad848c74f82130fd857d.

Change-Id: Icb8c787ebfa0e7dfd8289260225fef045fc1b0cb