[Remind-Fans] French translation optimization

[l0f4r0 at tuta.io]

Hi Laurent Duperval, the community,

Thank you very much for the french translation :)

I've added the following line in one of my remind files:
     INCLUDE [$SysInclude]/lang/fr.rem

But if I'm not mistaken, it seems there are still 2 places (maybe not exhaustive) where translation could be done in the `rem` output:

* Current date on 1st line
Example: "Reminders for Friday, 5th August, 2022 (today):"

* Substitution filters like %1
Examples: "Test alert 5 minutes ago" or "Test alert at 19:00 6 minutes from now"

NB: I could suggest to change the following function:
     FSET subst_ordinal(d) iif(d == 1, "er", "")
into:
     FSET subst_ordinal(d) iif(d == 1, "er", d == 2, "nd", "ème")
in order to take into account more french cases but there will still be an issue: the gender. Indeed, depending on the object counted, it can be masculine (1er, 2nd) or feminine (1ère, 2nde)... I'm not sure that could be scriptable. Otherwise, maybe put the following if it's not to bloated:
     FSET subst_ordinal(d) iif(d == 1, "er(e)", d == 2, "nd(e)", "ème")

 What do you think please?
Thanks in advance.
l0f4r0