(Pes) Add isNum to Num + Ord; fix bug in DetCN, DetQuant and DetQuantOrd

See https://sites.la.utexas.edu/persian_online_resources/nouns/

"A noun modified by a number is never pluralized; that is to say, it is 
invariably singular"

In the old grammar, DetQuant would always make the Det into numeral, and 
so Sg was always chosen in DetCN.

src/persian/CatPes.gf

@@ -59,9 +59,9 @@ concrete CatPes of Cat = CommonX - [Adv] ** open ResPes, Prelude in {
     Pron = {s : Str ; ps : Str ; a : AgrPes};
     Det = ResPes.Determiner ;
     Predet = {s : Str} ;
-    Num  = {s : Str ; n : Number} ;
+    Num  = {s : Str ; n : Number ; isNum : Bool} ;
     Card = {s : Str; n : Number} ;
-    Ord = {s : Str; n : Number} ;
+    Ord = {s : Str; n : Number ; isNum : Bool} ;
     Quant = {s: Number => Str ; a:AgrPes ; fromPron : Bool};
     Art = {s : Str} ;