Add Turkish language to preferences

Users of uk, vi, and wa languages will have to manually change their
lang on Windows after this.

src/fe-gtk/setup.c

@@ -134,6 +134,7 @@ static const char *const langsmenu[] =
 	N_("Spanish"),
 	N_("Swedish"),
 	N_("Thai"),
+	N_("Turkish"),
 	N_("Ukrainian"),
 	N_("Vietnamese"),
 	N_("Walloon"),